In Anno 1404, one of the primary means of earning income is through trade, however I can't seem to find a way to view details like the profits earned by each particular trade route in a consolidated manner. Without such a view, it is difficult to ascertain whether the shortfall of income through taxation could be offset by income from trade to maintain a positive cash flow. Is there such a view?
It looks like you're out of luck. The Rock, Paper, Shotgun review thinks it would be handy:
Additionally, a detailed balance sheet showing where things are going would have been very useful – there is sadly only a small “income in/out” detail on your main wallet.
but it doesn't actually exist. The rest of the review is here
Gameyum has a bit about budgeting taxes, building upkeep cost etc.
Balancing the budget requires constant attention to how much you're making. Dawn of Discovery thankfully makes this easy by including a small balance sheet which expands when you click on the part of the interface which shows how much money you have. The expanded balance sheet shows you how much you're making from taxes, how much you're spending on building upkeep, how much you're spending on ship upkeep, and how much you're losing to beggars (if any live in your city).
You can read their economy guide here
Dawn of Discovery is the American (and possibly other places) name for Anno 1404