How do horses from different parts of the world differ in diciplines, breeding cost, and popularity?

In order to answer this question I plan on answering the following questions:

1. How do costs in different countries differ when purchasing horses?
2. What are the top ten breeds in the U.S.?
3. The main diciplines in different places around the world?
4. What horses are good at which diciplines?

This is already what I know based on this topic:
I know that for show jumping and most dressage the prefered breed for these diciplines are the warmbloods imported from Europe. However, the cost of participating in the sport varies between where you are in the world.  I would to discover just how much it differs and which breeds do more service in different places.