Ill tell you what

Ill tell you one thing.... I love this game but im increasingly spending more time trying to make sure I don't go bankrupt or starve than I am having fun with the game..... one turn im 10k+ per turn then the next im negative or close......

Its annoying

That's a pretty big income swing for single turn. What faction are you playing?

The only time I've seen THAT big a swing in one turn has been playing as ERE, and WRE capital got besieged. This cut off our trade...and WRE-ERE trade is massive, I guess because the "long-time trade partner" bonus reflects that they've been trading for centuries (although, of course, that was really internal trade within a single empire).

WRE may be useless as an actual ally (like any AI faction, really), but it's in ERE's interest to keep WRE alive for the trade alone. More specifically, it's in ERE's interest to keep Mediolanum and Genua alive and un-besieged. After that hiccup, I've permanently kept one army stationed between the two cities (there's one spot by the river where one army can reinforce both simultaneously).

So if you see a really big unexplained drop, may want to check your long-time trade partners to see if their capital or port is blocked.

Im playing the Sassanids. Going for a military victory and trying to set up puppets because for some stupid reason you need them to win...... My puppets are all good and my regular trade partners don't seem to have any issues so I cant really tell whats up

There are significant seasonal swings in province fertility. During the seasons the fertility is up (usually the fall) you see higher income; then, when the fertility is down, you see a drop. There are other more random seasonal effects that affect income besides fertility too.

The same applies to your satraps. So, if their income tanks, what they pay to you gets smaller too.

Then there are trade blockades (a trade partner's city besieged, a trade route raided, etc.): all those can have a significant effect on income.

I think the effects that the seasons just add another dimension to this game.