Corporations Losing Cash (White Giant)

I feel noobish asking but I can't figure out why my corporations keep losing money. All of them used to be profitable, but now they keep making a loss each month, and that's really hurting my country's cash flow. Is it normal for them to start out good then start getting worse? I only have small worker shorteges, and I'm selling my products way above market price. Am I doing something wrong? Please help.

I'm on Tigerland on White Giant

It is possible, likely even, that the market price has fallen. Check the market demand situation (including clicking on the white underlining of the product, which will give more detailed information and link to graphs over time).

The good the corporation is selling and/or the goods the corporation uses, has changed in market prices. Is the most likely factor effecting profitability of a corporation.

Other factors may result in change of profitability of your individual corporation:
Loans
Salaries
Quality
Efficiency
Worker levels
Corporation contracts, or orders
If these factors have not change dramatically then its probably market price.

Factors that effect market price (basically have the largest effect on supply and demand):
Number of corporations selling the goods, and their production level (worker shortages, salaries will change this)
Previous factor noted but for corporations providing the raw materials.
Market floods: usually happens when a large country or empire is invaded, the invading player sells everything no matter what the price which usually results in a huge few months of oversupply causing the price to dramatically fall (it can sometimes take years for the market to correct its self. It can also happen if someone gets bored enough to stockpile a good then sell it all at the same time.
Huge order of good: opposite of market flood, usually happens with weapons or ammo during impending war, players may also buy a huge surplus of good to pick up a bargain.

Market volatility (how erratic supply and demand figures are) is higher for certain corporations then others. Highly volatile markets are not a good thing to invest in. If you check the history graphs that Keith noted, and there are large spikes and falls in market price and/or market situation its probably not a good idea to build that type of corporation if you feel you are not experienced enough to determine whether or not the corporation will be profitable.

Generally the market situation bar is a good indication on the current profitability of the product (under trade> products in stock), the higher the bar is in the red the higher the profitability of the corporation generally (note the volatility of the market as I stated though).

Hope I helped people determine what type of corporations to build.

Thanks for writing all that out, Angus. I was too lazy and/or tired to do that, especially considering the original post led me to believe that none of the corp's settings had changed.