You asked
I would like to request a table showing the household average income of families with children at private school, broken down by income quantile (or decile).
We said
Thank you for your request for information on the average income of families with children at private school.
The Family Resources Survey (FRS) collects some information on the education of children and would be the best source to answer your query. The FRS is owned by the Department for Work and Pensions (DWP) and you would need to contact them to see if the detail you require is available. Our surveys do not collect the information needed to answer your query.