To answer KKOB's post as though it was a genuine inquiry, my guess would be that there were many fewer "non-white" athletes in 1960 when we won 2 gold medals than there were in 1996 when we won 1. What has happened since then is an extraordinary development of British sporting achievement across a wide range of Olympic sports.
Well done to those who have competed so far and good luck to those whose hour is yet to come.