Hi there!
First, let me tell you, that this game is totally fun. I am a dev myself and I like the way you made your game and the various ways i can play it.
I played past the 30 years border and made quite a lot money on my bank, when i reached 21.998.239,9 M, the game crashed showing this message:
Uncaught TypeError: Cannot read property ‘cost’ of null
In the error message is most of the path to AppData/temp/…/codeNw.js but it is cut at the bottom.
BTW: I made that much by making a mix of Bioware and Blizzard, creating stellar RPG/Strategy games and going with 2 generic MMO’s (Fantasy/Sci-Fi) in the end. 
I guess MMO’s are not perfectly balanced for the system. I developed my own console for these 2 games and had 10M sales when the error occurred but sold >3.000 M units of one of the MMO’s (even if I get the same amount every month, that can’t be right).
Update:
It happens, when I scroll to fast through the Marketing options to get to Large Campaign. I just need to close Marketing and reopen it. Still weird.