The average "Index of Multiple Deprivation" [1] for Croydon is about 14,000, where every area (of some equal population size) is ranked from 1 to 32,884. Very roughly average for England.

Scotland isn't included, so I can't compare Strathclyde, but Blackpool's average is 5,900 — and includes 8 of the 10 most deprived places in the country.

Only one bit of London (part of Haringey) makes the top 1000. Only 106 bits of London (out of 4685) make the top 10%.

[1] https://www.gov.uk/government/statistics/english-indices-of-...