So I've been running my city for about a couple of months. In the beginning, I had a gain of $50k+ a week. Then, over the course of a few months, it plummeted to over $20k+ loss a week. I checked my "Budgets" panel and it showed that my commercial revenue went from ~$116k to ~$56k. The only thing I did was add more commercial (and a bit of industrial/offices) and changed the policies a bit to compensate for it saying "Not enough goods to sell!" and "Not enough buyers!" I tried turning off the day/night cycle because I saw that commercial buildings don't sell stuff in the night (unless After Dark DLC.) It didn't work. Please help, my money went from $5.5m to $1.6m very very fast.
I'm on PC.