For me is is all basically all United States. It's my bread and butter. I do get a little action from my UK players but the USA players spend more, lose more, and I make more. Keep in mind that I really only promote games and slots, that have better odds for me, and worse for the gambler.
In the sports betting sector I would think is a little bit different, like European football gets wagered on far more than the NFL, except horses. Americans can spend a fortune on horses. Take a look at my old man...