I don't recall seeing any data points on this subject, but given all the elite nights that Marriott has given away this year, I would be surprised if they gave out more. You should have got 13 for being Gold last year, 15-30 depending on whether you have 1 or 2 credit cards so you could have got 43 nights without spending a night in a hotel.

I agree with Xero. You have time to get 3 night in before year end. Find a cheap hotel, or something that doesn't require too many points. Good luck.