The internal review took the form of a number of submissions to Ministers. Advice to Ministers on the development and formulation of Government policy is not made public.
No; the cost of collecting and analyzing such statistics would far outweigh their usefulness. Collecting information would require significant changes to the information technology system, and the way our staff record information.
Additionally, as current immigration rules make it very unlikely that new polygamous households could be formed in the UK, and have done so since 1988, we know that the number of such households must be decreasing over time.