In Tropico 4, every industry building that has not been upgraded, in easy-does-it work mode, transforms input to output at the same rate. So a Furniture Factory with 8 workers requires 2 Lumber Mills with 4 workers each; this assumes all workers have an equal skill in the field. Upgrades/traits that increase production, do so without increasing required input. For example, a Furniture Factory with a Machining Center (+20% production), will transform 100 lumber into 120 furniture. The unit for trade prices is: money / 100 units. E.g. 100 coffee sells at 1300 money, with a trade price of 1300.