Pretty sure the difference is that I didn't include the IP we get from upgrading our 15 to a 16 and the 12 to a 15. Like I said in my post, more IP gives diminishing returns.I just did the math based on the spreadsheet, and maybe I'm missing something, but I only got a difference of 82.73 PP, presuming they're starting at the Infrastructure 3 planets and moving up from there.