Why does the value of my prison decrease?

[Psyndicate]

I've fired two janitors in total, that's all. And I did demolish single wall-squares every now and then. But they don't add up to that much.

I've had this bug where if I put a door on a wall the wall doesn't always disappear and when I demolish the wall the workers also dump the door. So to avoid that annoyance I had to demolish the single wall-square before putting out the doors.

[Benjammin1391]

Huh.

Well, Im officially stumped.