One measure is the amount of unclaimed benefits, which can amount to billions of pounds per year in the UK: https://www.bbc.co.uk/news/business-17139088 https:

One measure is the amount of unclaimed benefits, which can amount to billions of pounds per year in the UK: https://www.bbc.co.uk/news/business-17139088 https://www.bbc.co.uk/news/business-17139088