diff --git a/module3/exo3/exercice.ipynb b/module3/exo3/exercice.ipynb
index 0bbbe371b01e359e381e43239412d77bf53fb1fb..c45a1f3377a8a53a962a4625d8c86b7aca038b8e 100644
--- a/module3/exo3/exercice.ipynb
+++ b/module3/exo3/exercice.ipynb
@@ -1,6 +1,1127 @@
 {
- "cells": [],
+ "cells": [
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "hideCode": false,
+    "hidePrompt": false
+   },
+   "source": [
+    "# Concentration de CO2 dans l'atmosphère depuis 1958"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 1,
+   "metadata": {
+    "hideCode": false,
+    "hideOutput": true,
+    "hidePrompt": false
+   },
+   "outputs": [],
+   "source": [
+    "%matplotlib inline\n",
+    "import matplotlib.pyplot as plt\n",
+    "import pandas as pd\n",
+    "import isoweek"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    " Les données sont disponibles du site Web du [l'Institut Scripps](https://scrippsco2.ucsd.edu/data/atmospheric_co2/primary_mlo_co2_record.html). Nous les récupérons sous forme d'un fichier en format CSV dont chaque ligne correspond à une semaine de la période demandée. Nous téléchargeons toujours le jeu de données complet, qui commence en 1991 et se termine avec une semaine récente."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 2,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "data_url = \"https://scrippsco2.ucsd.edu/assets/data/atmospheric/stations/in_situ_co2/monthly/monthly_in_situ_co2_mlo.csv\""
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Pour nous protéger contre une éventuelle disparition ou modification du serveur du Réseau Sentinelles, nous faisons une copie locale de ce jeux de données que nous préservons avec notre analyse. Il est inutile et même risquée de télécharger les données à chaque exécution, car dans le cas d'une panne nous pourrions remplacer nos données par un fichier défectueux. Pour cette raison, nous téléchargeons les données seulement si la copie locale n'existe pas."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 3,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "data_file = \"concentration-co2.csv\"\n",
+    "\n",
+    "import os\n",
+    "import urllib.request\n",
+    "if not os.path.exists(data_file):\n",
+    "    urllib.request.urlretrieve(data_url, data_file)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Les 54 premières lignes du fichier CSV est un commentaire, que nous ignorons en précisant `skiprows=54`."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 4,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
+       "<div>\n",
+       "<style scoped>\n",
+       "    .dataframe tbody tr th:only-of-type {\n",
+       "        vertical-align: middle;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe tbody tr th {\n",
+       "        vertical-align: top;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe thead th {\n",
+       "        text-align: right;\n",
+       "    }\n",
+       "</style>\n",
+       "<table border=\"1\" class=\"dataframe\">\n",
+       "  <thead>\n",
+       "    <tr style=\"text-align: right;\">\n",
+       "      <th></th>\n",
+       "      <th>Yr</th>\n",
+       "      <th>Mn</th>\n",
+       "      <th>Date</th>\n",
+       "      <th>Date</th>\n",
+       "      <th>CO2</th>\n",
+       "      <th>seasonally</th>\n",
+       "      <th>fit</th>\n",
+       "      <th>seasonally</th>\n",
+       "      <th>CO2</th>\n",
+       "      <th>seasonally</th>\n",
+       "    </tr>\n",
+       "  </thead>\n",
+       "  <tbody>\n",
+       "    <tr>\n",
+       "      <th>0</th>\n",
+       "      <td></td>\n",
+       "      <td></td>\n",
+       "      <td></td>\n",
+       "      <td></td>\n",
+       "      <td></td>\n",
+       "      <td>adjusted</td>\n",
+       "      <td></td>\n",
+       "      <td>adjusted fit</td>\n",
+       "      <td>filled</td>\n",
+       "      <td>adjusted filled</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>1</th>\n",
+       "      <td></td>\n",
+       "      <td></td>\n",
+       "      <td>Excel</td>\n",
+       "      <td></td>\n",
+       "      <td>[ppm]</td>\n",
+       "      <td>[ppm]</td>\n",
+       "      <td>[ppm]</td>\n",
+       "      <td>[ppm]</td>\n",
+       "      <td>[ppm]</td>\n",
+       "      <td>[ppm]</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>2</th>\n",
+       "      <td>1958</td>\n",
+       "      <td>01</td>\n",
+       "      <td>21200</td>\n",
+       "      <td>1958.0411</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>3</th>\n",
+       "      <td>1958</td>\n",
+       "      <td>02</td>\n",
+       "      <td>21231</td>\n",
+       "      <td>1958.1260</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>4</th>\n",
+       "      <td>1958</td>\n",
+       "      <td>03</td>\n",
+       "      <td>21259</td>\n",
+       "      <td>1958.2027</td>\n",
+       "      <td>315.70</td>\n",
+       "      <td>314.44</td>\n",
+       "      <td>316.19</td>\n",
+       "      <td>314.91</td>\n",
+       "      <td>315.70</td>\n",
+       "      <td>314.44</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>5</th>\n",
+       "      <td>1958</td>\n",
+       "      <td>04</td>\n",
+       "      <td>21290</td>\n",
+       "      <td>1958.2877</td>\n",
+       "      <td>317.45</td>\n",
+       "      <td>315.16</td>\n",
+       "      <td>317.30</td>\n",
+       "      <td>314.99</td>\n",
+       "      <td>317.45</td>\n",
+       "      <td>315.16</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>6</th>\n",
+       "      <td>1958</td>\n",
+       "      <td>05</td>\n",
+       "      <td>21320</td>\n",
+       "      <td>1958.3699</td>\n",
+       "      <td>317.51</td>\n",
+       "      <td>314.71</td>\n",
+       "      <td>317.86</td>\n",
+       "      <td>315.06</td>\n",
+       "      <td>317.51</td>\n",
+       "      <td>314.71</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>7</th>\n",
+       "      <td>1958</td>\n",
+       "      <td>06</td>\n",
+       "      <td>21351</td>\n",
+       "      <td>1958.4548</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>317.24</td>\n",
+       "      <td>315.14</td>\n",
+       "      <td>317.24</td>\n",
+       "      <td>315.14</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>8</th>\n",
+       "      <td>1958</td>\n",
+       "      <td>07</td>\n",
+       "      <td>21381</td>\n",
+       "      <td>1958.5370</td>\n",
+       "      <td>315.86</td>\n",
+       "      <td>315.19</td>\n",
+       "      <td>315.86</td>\n",
+       "      <td>315.22</td>\n",
+       "      <td>315.86</td>\n",
+       "      <td>315.19</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>9</th>\n",
+       "      <td>1958</td>\n",
+       "      <td>08</td>\n",
+       "      <td>21412</td>\n",
+       "      <td>1958.6219</td>\n",
+       "      <td>314.93</td>\n",
+       "      <td>316.19</td>\n",
+       "      <td>314.00</td>\n",
+       "      <td>315.29</td>\n",
+       "      <td>314.93</td>\n",
+       "      <td>316.19</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>10</th>\n",
+       "      <td>1958</td>\n",
+       "      <td>09</td>\n",
+       "      <td>21443</td>\n",
+       "      <td>1958.7068</td>\n",
+       "      <td>313.21</td>\n",
+       "      <td>316.08</td>\n",
+       "      <td>312.46</td>\n",
+       "      <td>315.35</td>\n",
+       "      <td>313.21</td>\n",
+       "      <td>316.08</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>11</th>\n",
+       "      <td>1958</td>\n",
+       "      <td>10</td>\n",
+       "      <td>21473</td>\n",
+       "      <td>1958.7890</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>312.44</td>\n",
+       "      <td>315.40</td>\n",
+       "      <td>312.44</td>\n",
+       "      <td>315.40</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>12</th>\n",
+       "      <td>1958</td>\n",
+       "      <td>11</td>\n",
+       "      <td>21504</td>\n",
+       "      <td>1958.8740</td>\n",
+       "      <td>313.33</td>\n",
+       "      <td>315.20</td>\n",
+       "      <td>313.62</td>\n",
+       "      <td>315.46</td>\n",
+       "      <td>313.33</td>\n",
+       "      <td>315.20</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>13</th>\n",
+       "      <td>1958</td>\n",
+       "      <td>12</td>\n",
+       "      <td>21534</td>\n",
+       "      <td>1958.9562</td>\n",
+       "      <td>314.67</td>\n",
+       "      <td>315.43</td>\n",
+       "      <td>314.77</td>\n",
+       "      <td>315.51</td>\n",
+       "      <td>314.67</td>\n",
+       "      <td>315.43</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>14</th>\n",
+       "      <td>1959</td>\n",
+       "      <td>01</td>\n",
+       "      <td>21565</td>\n",
+       "      <td>1959.0411</td>\n",
+       "      <td>315.58</td>\n",
+       "      <td>315.54</td>\n",
+       "      <td>315.62</td>\n",
+       "      <td>315.57</td>\n",
+       "      <td>315.58</td>\n",
+       "      <td>315.54</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>15</th>\n",
+       "      <td>1959</td>\n",
+       "      <td>02</td>\n",
+       "      <td>21596</td>\n",
+       "      <td>1959.1260</td>\n",
+       "      <td>316.49</td>\n",
+       "      <td>315.86</td>\n",
+       "      <td>316.27</td>\n",
+       "      <td>315.63</td>\n",
+       "      <td>316.49</td>\n",
+       "      <td>315.86</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>16</th>\n",
+       "      <td>1959</td>\n",
+       "      <td>03</td>\n",
+       "      <td>21624</td>\n",
+       "      <td>1959.2027</td>\n",
+       "      <td>316.65</td>\n",
+       "      <td>315.38</td>\n",
+       "      <td>316.98</td>\n",
+       "      <td>315.69</td>\n",
+       "      <td>316.65</td>\n",
+       "      <td>315.38</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>17</th>\n",
+       "      <td>1959</td>\n",
+       "      <td>04</td>\n",
+       "      <td>21655</td>\n",
+       "      <td>1959.2877</td>\n",
+       "      <td>317.72</td>\n",
+       "      <td>315.42</td>\n",
+       "      <td>318.09</td>\n",
+       "      <td>315.77</td>\n",
+       "      <td>317.72</td>\n",
+       "      <td>315.42</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>18</th>\n",
+       "      <td>1959</td>\n",
+       "      <td>05</td>\n",
+       "      <td>21685</td>\n",
+       "      <td>1959.3699</td>\n",
+       "      <td>318.29</td>\n",
+       "      <td>315.49</td>\n",
+       "      <td>318.65</td>\n",
+       "      <td>315.85</td>\n",
+       "      <td>318.29</td>\n",
+       "      <td>315.49</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>19</th>\n",
+       "      <td>1959</td>\n",
+       "      <td>06</td>\n",
+       "      <td>21716</td>\n",
+       "      <td>1959.4548</td>\n",
+       "      <td>318.15</td>\n",
+       "      <td>316.03</td>\n",
+       "      <td>318.04</td>\n",
+       "      <td>315.94</td>\n",
+       "      <td>318.15</td>\n",
+       "      <td>316.03</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>20</th>\n",
+       "      <td>1959</td>\n",
+       "      <td>07</td>\n",
+       "      <td>21746</td>\n",
+       "      <td>1959.5370</td>\n",
+       "      <td>316.54</td>\n",
+       "      <td>315.86</td>\n",
+       "      <td>316.67</td>\n",
+       "      <td>316.03</td>\n",
+       "      <td>316.54</td>\n",
+       "      <td>315.86</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>21</th>\n",
+       "      <td>1959</td>\n",
+       "      <td>08</td>\n",
+       "      <td>21777</td>\n",
+       "      <td>1959.6219</td>\n",
+       "      <td>314.80</td>\n",
+       "      <td>316.06</td>\n",
+       "      <td>314.83</td>\n",
+       "      <td>316.12</td>\n",
+       "      <td>314.80</td>\n",
+       "      <td>316.06</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>22</th>\n",
+       "      <td>1959</td>\n",
+       "      <td>09</td>\n",
+       "      <td>21808</td>\n",
+       "      <td>1959.7068</td>\n",
+       "      <td>313.84</td>\n",
+       "      <td>316.72</td>\n",
+       "      <td>313.32</td>\n",
+       "      <td>316.22</td>\n",
+       "      <td>313.84</td>\n",
+       "      <td>316.72</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>23</th>\n",
+       "      <td>1959</td>\n",
+       "      <td>10</td>\n",
+       "      <td>21838</td>\n",
+       "      <td>1959.7890</td>\n",
+       "      <td>313.33</td>\n",
+       "      <td>316.32</td>\n",
+       "      <td>313.33</td>\n",
+       "      <td>316.30</td>\n",
+       "      <td>313.33</td>\n",
+       "      <td>316.32</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>24</th>\n",
+       "      <td>1959</td>\n",
+       "      <td>11</td>\n",
+       "      <td>21869</td>\n",
+       "      <td>1959.8740</td>\n",
+       "      <td>314.81</td>\n",
+       "      <td>316.68</td>\n",
+       "      <td>314.54</td>\n",
+       "      <td>316.39</td>\n",
+       "      <td>314.81</td>\n",
+       "      <td>316.68</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>25</th>\n",
+       "      <td>1959</td>\n",
+       "      <td>12</td>\n",
+       "      <td>21899</td>\n",
+       "      <td>1959.9562</td>\n",
+       "      <td>315.58</td>\n",
+       "      <td>316.35</td>\n",
+       "      <td>315.72</td>\n",
+       "      <td>316.47</td>\n",
+       "      <td>315.58</td>\n",
+       "      <td>316.35</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>26</th>\n",
+       "      <td>1960</td>\n",
+       "      <td>01</td>\n",
+       "      <td>21930</td>\n",
+       "      <td>1960.0410</td>\n",
+       "      <td>316.43</td>\n",
+       "      <td>316.39</td>\n",
+       "      <td>316.61</td>\n",
+       "      <td>316.56</td>\n",
+       "      <td>316.43</td>\n",
+       "      <td>316.39</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>27</th>\n",
+       "      <td>1960</td>\n",
+       "      <td>02</td>\n",
+       "      <td>21961</td>\n",
+       "      <td>1960.1257</td>\n",
+       "      <td>316.98</td>\n",
+       "      <td>316.35</td>\n",
+       "      <td>317.27</td>\n",
+       "      <td>316.64</td>\n",
+       "      <td>316.98</td>\n",
+       "      <td>316.35</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>28</th>\n",
+       "      <td>1960</td>\n",
+       "      <td>03</td>\n",
+       "      <td>21990</td>\n",
+       "      <td>1960.2049</td>\n",
+       "      <td>317.58</td>\n",
+       "      <td>316.28</td>\n",
+       "      <td>318.03</td>\n",
+       "      <td>316.71</td>\n",
+       "      <td>317.58</td>\n",
+       "      <td>316.28</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>29</th>\n",
+       "      <td>1960</td>\n",
+       "      <td>04</td>\n",
+       "      <td>22021</td>\n",
+       "      <td>1960.2896</td>\n",
+       "      <td>319.03</td>\n",
+       "      <td>316.70</td>\n",
+       "      <td>319.14</td>\n",
+       "      <td>316.79</td>\n",
+       "      <td>319.03</td>\n",
+       "      <td>316.70</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>...</th>\n",
+       "      <td>...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>...</td>\n",
+       "      <td>...</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>728</th>\n",
+       "      <td>2018</td>\n",
+       "      <td>07</td>\n",
+       "      <td>43296</td>\n",
+       "      <td>2018.5370</td>\n",
+       "      <td>408.90</td>\n",
+       "      <td>408.08</td>\n",
+       "      <td>409.43</td>\n",
+       "      <td>408.65</td>\n",
+       "      <td>408.90</td>\n",
+       "      <td>408.08</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>729</th>\n",
+       "      <td>2018</td>\n",
+       "      <td>08</td>\n",
+       "      <td>43327</td>\n",
+       "      <td>2018.6219</td>\n",
+       "      <td>407.10</td>\n",
+       "      <td>408.63</td>\n",
+       "      <td>407.33</td>\n",
+       "      <td>408.91</td>\n",
+       "      <td>407.10</td>\n",
+       "      <td>408.63</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>730</th>\n",
+       "      <td>2018</td>\n",
+       "      <td>09</td>\n",
+       "      <td>43358</td>\n",
+       "      <td>2018.7068</td>\n",
+       "      <td>405.59</td>\n",
+       "      <td>409.09</td>\n",
+       "      <td>405.66</td>\n",
+       "      <td>409.18</td>\n",
+       "      <td>405.59</td>\n",
+       "      <td>409.09</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>731</th>\n",
+       "      <td>2018</td>\n",
+       "      <td>10</td>\n",
+       "      <td>43388</td>\n",
+       "      <td>2018.7890</td>\n",
+       "      <td>405.99</td>\n",
+       "      <td>409.62</td>\n",
+       "      <td>405.83</td>\n",
+       "      <td>409.44</td>\n",
+       "      <td>405.99</td>\n",
+       "      <td>409.62</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>732</th>\n",
+       "      <td>2018</td>\n",
+       "      <td>11</td>\n",
+       "      <td>43419</td>\n",
+       "      <td>2018.8740</td>\n",
+       "      <td>408.12</td>\n",
+       "      <td>410.39</td>\n",
+       "      <td>407.47</td>\n",
+       "      <td>409.72</td>\n",
+       "      <td>408.12</td>\n",
+       "      <td>410.39</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>733</th>\n",
+       "      <td>2018</td>\n",
+       "      <td>12</td>\n",
+       "      <td>43449</td>\n",
+       "      <td>2018.9562</td>\n",
+       "      <td>409.23</td>\n",
+       "      <td>410.16</td>\n",
+       "      <td>409.07</td>\n",
+       "      <td>409.97</td>\n",
+       "      <td>409.23</td>\n",
+       "      <td>410.16</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>734</th>\n",
+       "      <td>2019</td>\n",
+       "      <td>01</td>\n",
+       "      <td>43480</td>\n",
+       "      <td>2019.0411</td>\n",
+       "      <td>410.92</td>\n",
+       "      <td>410.87</td>\n",
+       "      <td>410.29</td>\n",
+       "      <td>410.23</td>\n",
+       "      <td>410.92</td>\n",
+       "      <td>410.87</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>735</th>\n",
+       "      <td>2019</td>\n",
+       "      <td>02</td>\n",
+       "      <td>43511</td>\n",
+       "      <td>2019.1260</td>\n",
+       "      <td>411.66</td>\n",
+       "      <td>410.90</td>\n",
+       "      <td>411.24</td>\n",
+       "      <td>410.47</td>\n",
+       "      <td>411.66</td>\n",
+       "      <td>410.90</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>736</th>\n",
+       "      <td>2019</td>\n",
+       "      <td>03</td>\n",
+       "      <td>43539</td>\n",
+       "      <td>2019.2027</td>\n",
+       "      <td>412.00</td>\n",
+       "      <td>410.45</td>\n",
+       "      <td>412.25</td>\n",
+       "      <td>410.68</td>\n",
+       "      <td>412.00</td>\n",
+       "      <td>410.45</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>737</th>\n",
+       "      <td>2019</td>\n",
+       "      <td>04</td>\n",
+       "      <td>43570</td>\n",
+       "      <td>2019.2877</td>\n",
+       "      <td>413.52</td>\n",
+       "      <td>410.72</td>\n",
+       "      <td>413.73</td>\n",
+       "      <td>410.91</td>\n",
+       "      <td>413.52</td>\n",
+       "      <td>410.72</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>738</th>\n",
+       "      <td>2019</td>\n",
+       "      <td>05</td>\n",
+       "      <td>43600</td>\n",
+       "      <td>2019.3699</td>\n",
+       "      <td>414.83</td>\n",
+       "      <td>411.42</td>\n",
+       "      <td>414.54</td>\n",
+       "      <td>411.13</td>\n",
+       "      <td>414.83</td>\n",
+       "      <td>411.42</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>739</th>\n",
+       "      <td>2019</td>\n",
+       "      <td>06</td>\n",
+       "      <td>43631</td>\n",
+       "      <td>2019.4548</td>\n",
+       "      <td>413.96</td>\n",
+       "      <td>411.38</td>\n",
+       "      <td>413.91</td>\n",
+       "      <td>411.35</td>\n",
+       "      <td>413.96</td>\n",
+       "      <td>411.38</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>740</th>\n",
+       "      <td>2019</td>\n",
+       "      <td>07</td>\n",
+       "      <td>43661</td>\n",
+       "      <td>2019.5370</td>\n",
+       "      <td>411.85</td>\n",
+       "      <td>411.03</td>\n",
+       "      <td>412.36</td>\n",
+       "      <td>411.57</td>\n",
+       "      <td>411.85</td>\n",
+       "      <td>411.03</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>741</th>\n",
+       "      <td>2019</td>\n",
+       "      <td>08</td>\n",
+       "      <td>43692</td>\n",
+       "      <td>2019.6219</td>\n",
+       "      <td>410.08</td>\n",
+       "      <td>411.62</td>\n",
+       "      <td>410.23</td>\n",
+       "      <td>411.81</td>\n",
+       "      <td>410.08</td>\n",
+       "      <td>411.62</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>742</th>\n",
+       "      <td>2019</td>\n",
+       "      <td>09</td>\n",
+       "      <td>43723</td>\n",
+       "      <td>2019.7068</td>\n",
+       "      <td>408.55</td>\n",
+       "      <td>412.06</td>\n",
+       "      <td>408.52</td>\n",
+       "      <td>412.05</td>\n",
+       "      <td>408.55</td>\n",
+       "      <td>412.06</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>743</th>\n",
+       "      <td>2019</td>\n",
+       "      <td>10</td>\n",
+       "      <td>43753</td>\n",
+       "      <td>2019.7890</td>\n",
+       "      <td>408.43</td>\n",
+       "      <td>412.07</td>\n",
+       "      <td>408.67</td>\n",
+       "      <td>412.29</td>\n",
+       "      <td>408.43</td>\n",
+       "      <td>412.07</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>744</th>\n",
+       "      <td>2019</td>\n",
+       "      <td>11</td>\n",
+       "      <td>43784</td>\n",
+       "      <td>2019.8740</td>\n",
+       "      <td>410.28</td>\n",
+       "      <td>412.56</td>\n",
+       "      <td>410.29</td>\n",
+       "      <td>412.54</td>\n",
+       "      <td>410.28</td>\n",
+       "      <td>412.56</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>745</th>\n",
+       "      <td>2019</td>\n",
+       "      <td>12</td>\n",
+       "      <td>43814</td>\n",
+       "      <td>2019.9562</td>\n",
+       "      <td>411.85</td>\n",
+       "      <td>412.78</td>\n",
+       "      <td>411.88</td>\n",
+       "      <td>412.79</td>\n",
+       "      <td>411.85</td>\n",
+       "      <td>412.78</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>746</th>\n",
+       "      <td>2020</td>\n",
+       "      <td>01</td>\n",
+       "      <td>43845</td>\n",
+       "      <td>2020.0410</td>\n",
+       "      <td>413.37</td>\n",
+       "      <td>413.33</td>\n",
+       "      <td>413.11</td>\n",
+       "      <td>413.05</td>\n",
+       "      <td>413.37</td>\n",
+       "      <td>413.33</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>747</th>\n",
+       "      <td>2020</td>\n",
+       "      <td>02</td>\n",
+       "      <td>43876</td>\n",
+       "      <td>2020.1257</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>748</th>\n",
+       "      <td>2020</td>\n",
+       "      <td>03</td>\n",
+       "      <td>43905</td>\n",
+       "      <td>2020.2049</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>749</th>\n",
+       "      <td>2020</td>\n",
+       "      <td>04</td>\n",
+       "      <td>43936</td>\n",
+       "      <td>2020.2896</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>750</th>\n",
+       "      <td>2020</td>\n",
+       "      <td>05</td>\n",
+       "      <td>43966</td>\n",
+       "      <td>2020.3716</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>751</th>\n",
+       "      <td>2020</td>\n",
+       "      <td>06</td>\n",
+       "      <td>43997</td>\n",
+       "      <td>2020.4563</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>752</th>\n",
+       "      <td>2020</td>\n",
+       "      <td>07</td>\n",
+       "      <td>44027</td>\n",
+       "      <td>2020.5383</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>753</th>\n",
+       "      <td>2020</td>\n",
+       "      <td>08</td>\n",
+       "      <td>44058</td>\n",
+       "      <td>2020.6230</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>754</th>\n",
+       "      <td>2020</td>\n",
+       "      <td>09</td>\n",
+       "      <td>44089</td>\n",
+       "      <td>2020.7077</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>755</th>\n",
+       "      <td>2020</td>\n",
+       "      <td>10</td>\n",
+       "      <td>44119</td>\n",
+       "      <td>2020.7896</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>756</th>\n",
+       "      <td>2020</td>\n",
+       "      <td>11</td>\n",
+       "      <td>44150</td>\n",
+       "      <td>2020.8743</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "    </tr>\n",
+       "    <tr>\n",
+       "      <th>757</th>\n",
+       "      <td>2020</td>\n",
+       "      <td>12</td>\n",
+       "      <td>44180</td>\n",
+       "      <td>2020.9563</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "      <td>-99.99</td>\n",
+       "    </tr>\n",
+       "  </tbody>\n",
+       "</table>\n",
+       "<p>758 rows × 10 columns</p>\n",
+       "</div>"
+      ],
+      "text/plain": [
+       "       Yr   Mn      Date        Date        CO2  seasonally          fit  \\\n",
+       "0                                                  adjusted                \n",
+       "1                  Excel                  [ppm]      [ppm]         [ppm]   \n",
+       "2    1958   01     21200   1958.0411     -99.99      -99.99       -99.99   \n",
+       "3    1958   02     21231   1958.1260     -99.99      -99.99       -99.99   \n",
+       "4    1958   03     21259   1958.2027     315.70      314.44       316.19   \n",
+       "5    1958   04     21290   1958.2877     317.45      315.16       317.30   \n",
+       "6    1958   05     21320   1958.3699     317.51      314.71       317.86   \n",
+       "7    1958   06     21351   1958.4548     -99.99      -99.99       317.24   \n",
+       "8    1958   07     21381   1958.5370     315.86      315.19       315.86   \n",
+       "9    1958   08     21412   1958.6219     314.93      316.19       314.00   \n",
+       "10   1958   09     21443   1958.7068     313.21      316.08       312.46   \n",
+       "11   1958   10     21473   1958.7890     -99.99      -99.99       312.44   \n",
+       "12   1958   11     21504   1958.8740     313.33      315.20       313.62   \n",
+       "13   1958   12     21534   1958.9562     314.67      315.43       314.77   \n",
+       "14   1959   01     21565   1959.0411     315.58      315.54       315.62   \n",
+       "15   1959   02     21596   1959.1260     316.49      315.86       316.27   \n",
+       "16   1959   03     21624   1959.2027     316.65      315.38       316.98   \n",
+       "17   1959   04     21655   1959.2877     317.72      315.42       318.09   \n",
+       "18   1959   05     21685   1959.3699     318.29      315.49       318.65   \n",
+       "19   1959   06     21716   1959.4548     318.15      316.03       318.04   \n",
+       "20   1959   07     21746   1959.5370     316.54      315.86       316.67   \n",
+       "21   1959   08     21777   1959.6219     314.80      316.06       314.83   \n",
+       "22   1959   09     21808   1959.7068     313.84      316.72       313.32   \n",
+       "23   1959   10     21838   1959.7890     313.33      316.32       313.33   \n",
+       "24   1959   11     21869   1959.8740     314.81      316.68       314.54   \n",
+       "25   1959   12     21899   1959.9562     315.58      316.35       315.72   \n",
+       "26   1960   01     21930   1960.0410     316.43      316.39       316.61   \n",
+       "27   1960   02     21961   1960.1257     316.98      316.35       317.27   \n",
+       "28   1960   03     21990   1960.2049     317.58      316.28       318.03   \n",
+       "29   1960   04     22021   1960.2896     319.03      316.70       319.14   \n",
+       "..    ...  ...       ...         ...        ...         ...          ...   \n",
+       "728  2018   07     43296   2018.5370     408.90      408.08       409.43   \n",
+       "729  2018   08     43327   2018.6219     407.10      408.63       407.33   \n",
+       "730  2018   09     43358   2018.7068     405.59      409.09       405.66   \n",
+       "731  2018   10     43388   2018.7890     405.99      409.62       405.83   \n",
+       "732  2018   11     43419   2018.8740     408.12      410.39       407.47   \n",
+       "733  2018   12     43449   2018.9562     409.23      410.16       409.07   \n",
+       "734  2019   01     43480   2019.0411     410.92      410.87       410.29   \n",
+       "735  2019   02     43511   2019.1260     411.66      410.90       411.24   \n",
+       "736  2019   03     43539   2019.2027     412.00      410.45       412.25   \n",
+       "737  2019   04     43570   2019.2877     413.52      410.72       413.73   \n",
+       "738  2019   05     43600   2019.3699     414.83      411.42       414.54   \n",
+       "739  2019   06     43631   2019.4548     413.96      411.38       413.91   \n",
+       "740  2019   07     43661   2019.5370     411.85      411.03       412.36   \n",
+       "741  2019   08     43692   2019.6219     410.08      411.62       410.23   \n",
+       "742  2019   09     43723   2019.7068     408.55      412.06       408.52   \n",
+       "743  2019   10     43753   2019.7890     408.43      412.07       408.67   \n",
+       "744  2019   11     43784   2019.8740     410.28      412.56       410.29   \n",
+       "745  2019   12     43814   2019.9562     411.85      412.78       411.88   \n",
+       "746  2020   01     43845   2020.0410     413.37      413.33       413.11   \n",
+       "747  2020   02     43876   2020.1257     -99.99      -99.99       -99.99   \n",
+       "748  2020   03     43905   2020.2049     -99.99      -99.99       -99.99   \n",
+       "749  2020   04     43936   2020.2896     -99.99      -99.99       -99.99   \n",
+       "750  2020   05     43966   2020.3716     -99.99      -99.99       -99.99   \n",
+       "751  2020   06     43997   2020.4563     -99.99      -99.99       -99.99   \n",
+       "752  2020   07     44027   2020.5383     -99.99      -99.99       -99.99   \n",
+       "753  2020   08     44058   2020.6230     -99.99      -99.99       -99.99   \n",
+       "754  2020   09     44089   2020.7077     -99.99      -99.99       -99.99   \n",
+       "755  2020   10     44119   2020.7896     -99.99      -99.99       -99.99   \n",
+       "756  2020   11     44150   2020.8743     -99.99      -99.99       -99.99   \n",
+       "757  2020   12     44180   2020.9563     -99.99      -99.99       -99.99   \n",
+       "\n",
+       "       seasonally           CO2       seasonally  \n",
+       "0    adjusted fit        filled  adjusted filled  \n",
+       "1           [ppm]         [ppm]            [ppm]  \n",
+       "2          -99.99        -99.99           -99.99  \n",
+       "3          -99.99        -99.99           -99.99  \n",
+       "4          314.91        315.70           314.44  \n",
+       "5          314.99        317.45           315.16  \n",
+       "6          315.06        317.51           314.71  \n",
+       "7          315.14        317.24           315.14  \n",
+       "8          315.22        315.86           315.19  \n",
+       "9          315.29        314.93           316.19  \n",
+       "10         315.35        313.21           316.08  \n",
+       "11         315.40        312.44           315.40  \n",
+       "12         315.46        313.33           315.20  \n",
+       "13         315.51        314.67           315.43  \n",
+       "14         315.57        315.58           315.54  \n",
+       "15         315.63        316.49           315.86  \n",
+       "16         315.69        316.65           315.38  \n",
+       "17         315.77        317.72           315.42  \n",
+       "18         315.85        318.29           315.49  \n",
+       "19         315.94        318.15           316.03  \n",
+       "20         316.03        316.54           315.86  \n",
+       "21         316.12        314.80           316.06  \n",
+       "22         316.22        313.84           316.72  \n",
+       "23         316.30        313.33           316.32  \n",
+       "24         316.39        314.81           316.68  \n",
+       "25         316.47        315.58           316.35  \n",
+       "26         316.56        316.43           316.39  \n",
+       "27         316.64        316.98           316.35  \n",
+       "28         316.71        317.58           316.28  \n",
+       "29         316.79        319.03           316.70  \n",
+       "..            ...           ...              ...  \n",
+       "728        408.65        408.90           408.08  \n",
+       "729        408.91        407.10           408.63  \n",
+       "730        409.18        405.59           409.09  \n",
+       "731        409.44        405.99           409.62  \n",
+       "732        409.72        408.12           410.39  \n",
+       "733        409.97        409.23           410.16  \n",
+       "734        410.23        410.92           410.87  \n",
+       "735        410.47        411.66           410.90  \n",
+       "736        410.68        412.00           410.45  \n",
+       "737        410.91        413.52           410.72  \n",
+       "738        411.13        414.83           411.42  \n",
+       "739        411.35        413.96           411.38  \n",
+       "740        411.57        411.85           411.03  \n",
+       "741        411.81        410.08           411.62  \n",
+       "742        412.05        408.55           412.06  \n",
+       "743        412.29        408.43           412.07  \n",
+       "744        412.54        410.28           412.56  \n",
+       "745        412.79        411.85           412.78  \n",
+       "746        413.05        413.37           413.33  \n",
+       "747        -99.99        -99.99           -99.99  \n",
+       "748        -99.99        -99.99           -99.99  \n",
+       "749        -99.99        -99.99           -99.99  \n",
+       "750        -99.99        -99.99           -99.99  \n",
+       "751        -99.99        -99.99           -99.99  \n",
+       "752        -99.99        -99.99           -99.99  \n",
+       "753        -99.99        -99.99           -99.99  \n",
+       "754        -99.99        -99.99           -99.99  \n",
+       "755        -99.99        -99.99           -99.99  \n",
+       "756        -99.99        -99.99           -99.99  \n",
+       "757        -99.99        -99.99           -99.99  \n",
+       "\n",
+       "[758 rows x 10 columns]"
+      ]
+     },
+     "execution_count": 4,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "raw_data = pd.read_csv(data_file, skiprows=54)\n",
+    "raw_data"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "Vérifions si nous avons des points manquants dans ce jeu de données."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 5,
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/html": [
+       "<div>\n",
+       "<style scoped>\n",
+       "    .dataframe tbody tr th:only-of-type {\n",
+       "        vertical-align: middle;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe tbody tr th {\n",
+       "        vertical-align: top;\n",
+       "    }\n",
+       "\n",
+       "    .dataframe thead th {\n",
+       "        text-align: right;\n",
+       "    }\n",
+       "</style>\n",
+       "<table border=\"1\" class=\"dataframe\">\n",
+       "  <thead>\n",
+       "    <tr style=\"text-align: right;\">\n",
+       "      <th></th>\n",
+       "      <th>Yr</th>\n",
+       "      <th>Mn</th>\n",
+       "      <th>Date</th>\n",
+       "      <th>Date</th>\n",
+       "      <th>CO2</th>\n",
+       "      <th>seasonally</th>\n",
+       "      <th>fit</th>\n",
+       "      <th>seasonally</th>\n",
+       "      <th>CO2</th>\n",
+       "      <th>seasonally</th>\n",
+       "    </tr>\n",
+       "  </thead>\n",
+       "  <tbody>\n",
+       "  </tbody>\n",
+       "</table>\n",
+       "</div>"
+      ],
+      "text/plain": [
+       "Empty DataFrame\n",
+       "Columns: [  Yr,  Mn,     Date,       Date,      CO2, seasonally,         fit,   seasonally,       CO2,  seasonally]\n",
+       "Index: []"
+      ]
+     },
+     "execution_count": 5,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "raw_data[raw_data.isnull().any(axis=1)]"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  }
+ ],
  "metadata": {
+  "hide_code_all_hidden": false,
   "kernelspec": {
    "display_name": "Python 3",
    "language": "python",
@@ -16,10 +1137,9 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.6.3"
+   "version": "3.6.4"
   }
  },
  "nbformat": 4,
  "nbformat_minor": 2
 }
-