The KPMG Annual Financial Institutions Performance Survey is always worth looking at.
There is a separate section on building societies and credit unions .
The key ratios used are in themselves interesting: whilst the number of members is a reported statistic, the report does not create ratios using that information.
Excluding credit unions that have merged, a number of credit unions have actually reported a decrease in the number of members whilst at the same time reporting an increase in assets. This is most likely the result of a dormant accounts program, which allows a credit union to focus on active members by closing inactive accounts.