'A free market is a market system in which the prices for goods and services are set freely by consent between vendors and consumers, in which the laws and forces of supply and demand are free from any intervention by a government, price-setting monopoly, or other authority.'
So if supply is higher then demand, for example a kind of unlimited number of taxi's, then the prices go down.
I think in theory with easy entrance to a market the prices can drop as low as variable costs. But I cannot find a reference to that at the moment.
