The figure has been falling since the 'crisis' of 2008, but the number of Britons registered as living in Spain (town hall padrón figures at the statistics institute, the INE) has actually risen in the past twelve months by over 4,000. The official figures have gone from 236,669 to 240,934 as of January 1st 2018. An increase of over 1.8%. Something to do with the Brexit? Probably.
(A suitably horrible picture, to save the Press finding one of us all drinking in a bar full of Union flags).
All nationalities are here.