Art Collector Report 2014 -  14,99 USD (e-pub)

The United States has the largest share of art collectors worldwide with 25%, followed by Germany with 9% and the UK and China with 7% each.
The biggest collector city is New York with 9% of global collectors. London (6%) and Sao Paulo (3%) rank second and third.
The average age of a collector is 59 years. 71 % of collectors are men.
https://www.larryslist.com/art-collector-report/