Statistical significance on aggregate data to show that the groups are different?

Question

I am working with performance data for three groups for each region. The denominator for the groups is the number of people who are identified as low performers. For region A, Group-1 low performer %= 40% , group-2= 30% , group-3 low performer= 30%. Similar data for 10 more regions. Now, I want to highlight where the groups have a higher low performer ratio than other groups in each region, but instead of an arbitrary threshold, want to run a statistical significance test. Please advise on what test I can use. I need to do the same with the denominator for the headcount for each group in a region as well as a second use-case.