I've seen that chart mentioned in:
Does Penis Size Matter? The End of the Penis Size Debate
If you have read that biased, bullshit site which has many links to penis enlargement products etc, you will take that chart with a pinch of salt.
Given the amount of men in the world with the ideal size (< 5% of the world's male population), I wonder how many women, if any, where tested and under what conditions.
By the "results" it looks like only a small group of size queens might have been questioned.