Historical Aggregated Top 5 Savings Interest Rates?

[tlf67482]

Does anyone know of a source for historical yearly (or even monthly) savings interest rates that aggregates a certain number of top providers rates? It doesn't need to be massively precise, it could be the top 10 (or whatever) just anything better than having to use the rate of inflation which doesn't really have any correlation to savings rates.

I do remember a UK site called Swanlow (or something?) that had this information but I can't find it.

Thanks

Example (completely made up figures):

Average of the top 5 interest paying easy access savings accounts
January 2024: 5%
December 2023: 4.75%
November 2023: 4.75%
October 2023: 4.5%
...
...
December 2010: 2.8%
...
...
December 1998: 6%
December 1997: 4%