How Many Ethnic Groups Are There In United Kingdom?

In the United Kingdom, you have something called race code identity, which was replaced earlier by racial groups. The race code applied are as follows, IC1 for White person, IC2 for Mediterranean or Hispanic person, IC3 for  African/Caribbean person,  IC4 for  Indian, Pakistani, Bangladeshi, or any other Asian person,  IC5 for  Chinese, Japanese, or South-East Asian person, IC6 for  Arabic, Egyptian or Maghreb person and IC0 for  Origin unknown.

However, since April 1st, 2003 they were 16 more ethnic codes recorded, which were W1 for White British, W2 for White Irish, W9 for any other white background, M1 for Mixed White and Black Caribbean, M2 for Mixed White and Black African, M3 for Mixed White and Asian, M9 for any other mixed background, A1 for Asian - Indian

A2 for Asian – Pakistani, A3 for Asian – Bangladeshi, A9 for any other Asian background, B1 for Caribbean, B2 for African, B9 for any other black background,
O1 for Chinese, O9 for any other ethnic group and NS for not stated.