Placid, why use percentages, and why use them in that manner? It curiously punishes countries that excell while rewards countries that lag. If one country has 500 atheletes of comparable quality and skill to another countries 20, why should the gold medals that the former wins be presented as having less worth than the gold medals of the latter?
An alternate method of percentages would be to have medals won out of total possible. That is, if there are 200 events at the olympics and a country wins 50 gold medals, then they have a 25% gold medal rate. Perfectly equitable.