I have 30 charts that were created from excel and were pasted onto powerpoint slides. Every month, I have to update these 30 embedded charts by manually clicking on the char
This is fairly easily accomplished, without any VBA code required.
Click the "Office Button", select "Edit Links to File" (it's beneath "Run Compatibility Check", you will have to scroll down to see that last option):
Select all embedded charts (referred to here as "links"), click "Update Now":
You can use the same window to break links, as well as to change the source file for any given link.