<!DOCTYPE html> <html> <head> <title>WEEKNUM Function</title> <meta charset="utf-8" /> <meta name="description" content="" /> <link type="text/css" rel="stylesheet" href="../editor.css" /> <link type = "text/css" rel = "stylesheet" href = "../../images/sprite.css" /> <script type="text/javascript" src="../callback.js"></script> <script type="text/javascript" src="../search/js/page-search.js"></script> </head> <body> <div class="mainpart"> <div class="search-field"> <input id="search" class="searchBar" placeholder="Search" type="text" onkeypress="doSearch(event)"> </div> <h1>WEEKNUM Function</h1> <p>The <b>WEEKNUM</b> function is one of the date and time functions. It used to return the number of the week the specified date falls within the year.</p> <p>The <b>WEEKNUM</b> function syntax is:</p> <p style="text-indent: 150px;"><b><em>WEEKNUM(serial_number, [return_type])</em></b></p> <p><em>where</em></p> <p style="text-indent: 50px;"><b><em>serial_number</em></b> is a number representing the date within the week, entered using the <a href="Date.htm" onclick="onhyperlinkclick(this)">Date</a> function or other date and time function.</p> <p style="text-indent: 50px;"><b><em>return_type</em></b> is a numeric value used to determine on which day the week begins. It can be one of the following:</p> <table style="width: 40%"> <tr> <td><b>Numeric value</b></td> <td><b>Week begins on</b></td> <td><b>System</b></td> </tr> <tr> <td>1 or omitted</td> <td>Sunday</td> <td>1</td> </tr> <tr> <td>2</td> <td>Monday</td> <td>1</td> </tr> <tr> <td>11</td> <td>Monday</td> <td>1</td> </tr> <tr> <td>12</td> <td>Tuesday</td> <td>1</td> </tr> <tr> <td>13</td> <td>Wednesday</td> <td>1</td> </tr> <tr> <td>14</td> <td>Thursday</td> <td>1</td> </tr> <tr> <td>15</td> <td>Friday</td> <td>1</td> </tr> <tr> <td>16</td> <td>Saturday</td> <td>1</td> </tr> <tr> <td>17</td> <td>Sunday</td> <td>1</td> </tr> <tr> <td>21</td> <td>Monday</td> <td>2</td> </tr> </table> <p>When <b><em>return_type</em></b> is set to 1-17, <b>System 1</b> is used. This means that the first week in a year is the week that contains January 1.</p> <p>When <b><em>return_type</em></b> is set to 21, <b>System 2</b> is used. This means that the first week in a year is the week that contains the first Thursday of the year. System 2 is commonly used in Europe according to the ISO 8601 standard.</p> <p>To apply the <b>WEEKNUM</b> function,</p> <ol> <li>select the cell where you wish to display the result,</li> <li>click the <b>Insert function</b> <div class = "icon icon-insertfunction"></div> icon situated at the top toolbar, <br />or right-click within a selected cell and select the <b>Insert Function</b> option from the menu, <br />or click the <div class = "icon icon-function"></div> icon situated at the formula bar, </li> <li>select the <b>Date and time</b> function group from the list,</li> <li>click the <b>WEEKNUM</b> function,</li> <li>enter the required arguments separating them by commas,</li> <li>press the <b>Enter</b> button.</li> </ol> <p>The result will be displayed in the selected cell.</p> <p style="text-indent: 150px;"><img alt="WEEKNUM Function" src="../images/weeknum.png" /></p> </div> </body> </html>