I don’t have any stats since, it is not something they keep track of (For obvious reasons) but I remember when I used to frequent various Middle East forums, it was talked about how prevalent it was:
Searching out of memory, there is a local saying in Afghanistan that Birds fly above Kandahar using only one wing because they are using the other to cover their behinds.
One can only speculate about the roots of sodomy and homosexuality in Afghanistan because the fact is that a long-standing tradition is always the result of various factors. Some claim that the main reason for this is the ban of any contact between men and women who are not married, while men constantly spend time together.
In the city of Kandahar, which is considered the gay capital of Southern Asia, there is an ancient custom among the ethnic Pashtun people. An adult man picks a young boy, a teenager, called an “ashna” and gives him money and presents in turn for sexual favours. This Pashtun tradition is even represented in their poetry, in odes written about the beauty of young “ashnas”. This is a tradition that is present in all facets of society, practiced by the rich and poor alike. The parents of young boys who are sex slaves are usually aware of their sons’ relations with their “sugar daddies”. And although their parents keep this a secret from others, they do not contest the custom. Especially if the Pashtun is rich.