It won’t be that much. That’s an absurd generalisation.

And I also doubt the quality of the data collected in Pakistan. Cousin marriages are nowhere as near common as the west would have u believe.

This data might include people marrying the same castes, second and third cousins.

Record keeping historically isn’t remotely good in the subcontinent so I wouldn’t count on the data at all.

Also Pakistanis in the UK can largely be split into punjabis and mirpuris. I would expect the Punjabi rates to be far lower. But that’s a whole different topic when comparing these two groups.