Microsoft introduced Chart Web Part in SharePoint 2010. It is a very useful web part to work with for different scenarios. But as Microsoft removed some of the 2010 features in SharePoint 2013, Chart web part is also removed by Microsoft in SharePoint 2013.
But still you can add the chart web part in SharePoint 2013. Follow below steps.
Download this file and then unzip it.
Edit the page and then go to the INSERT tab and then there click on Web Part. Then click on Upload a Web Part and then browser the file that we have unziped in Step-1 and click on Upload as shown in the fig below:
Then the Chat web part will come in the web part list, select the web part and click on OK. It will appear in the page as shown in the fig below:
Hope it will be helpful to you.