PowerPoint Chart templates can be very useful within your organization. This feature is available in powerpoint 2010 as we could see in How to Use Chart templates in powerpoint, however if you are moving to powerpoint 2013, you will notice that Save As Template option is not available in the same Design tab that it used to be.
To Save a Chart Template in powerpoint 2013, you will need to right click on the Chart and then look for Save as Template in the contextual menu. Clicking here you can specify the location for the .crtx file name with your Microsoft Office powerpoint Chart template.
For any reason, Microsoft thought that this feature do not deserved a space in the Chart Design menu, but of course you can customize it to the old location Customizing the Toolbar.