This reminds me of the Total War series of games, where you control an empire (a bit like civilization) in a very realistic way. The bigger your empire, the bigger percentage of your money gets burnt by corruption. Also, the longer your governors are in place, the more corrupt they become, so even if they were very competent to start with, they end up making more harm than good, so you want to change them once in a while. It's not a parameter you can work on, it's just a fact. Learn to deal with it.
That's not a trend, that's an inevitability. Government has power and power corrupts.
This reminds me of the Total War series of games, where you control an empire (a bit like civilization) in a very realistic way. The bigger your empire, the bigger percentage of your money gets burnt by corruption. Also, the longer your governors are in place, the more corrupt they become, so even if they were very competent to start with, they end up making more harm than good, so you want to change them once in a while. It's not a parameter you can work on, it's just a fact. Learn to deal with it.