I am not sure which particular axe you are grinding here. Could you be a little more specific?
Old Victoria, early versions.:
IE. Uruguay, steel plant
You pay 100% value of raw materials from national budget to produce steel
You have 25% tax
You recieve 25% product value into your budget, which can be less than the value of raw materials it takes to produce steel.
Bottom line, your workers are more productive than as ranchers, but you lose money, and since high taxes had other negative effects, raising taxes above 50% was kinda suicidal.
A more mathematic approach:
Uruguay as farmers make 3 money, 25% of that is 0,75, so you make 0,75 into treasuary
Uruguay as steel workers make 16 money, but eat 5 worth of coal and iron making a net effect of 11, but due to how the tax and imports worked, you get 25% of 16, which is 4 and pay 5, so with same tax, higher industrial output, you make a net into treasuary of -1. Now if you introduced a tax of 50% you made 8, a net of +3, and your workers still made 8 instead of 2,25, but were more likely to revolt or degrade to farmers and stuff.