Answer based on context:

Between 2001 and 2011, the greatest nominal population increase was in the White, Other group from 3,780 to 13,825 – an increase of 10,045 – likely due to migration from Eastern Europe. The largest growth relative to their 2001 numbers was in the Black, African group, recording a 376% increase from 1,361 to 6,473. The largest nominal fall in population was in respondents reporting as White, British, there being 8,146 fewer such residents in 2011 than 10 years previous. The largest fall relative to their 2001 numbers was in the White, Irish group, their count falling 20.3% from 3,838 down to 3,060.

Which saw a bigger increase in population, White, other group or Black, African group?
White, Other group