The Government Says

Number of active SIA licences in 2 sectors each year since 2011

Number of active SIA licences in 2 sectors each year since 2011
Local copy of sia-cctv-licences-since-2011.csv
Local copy of sia-sg-licences-since-2011.csv

https://www.gov.uk/government/publications/number-of-active-sia-licences-in-2-sectors-each-year-since-2011

seen at 11:32, 29 May in Transparency and freedom of information releases.