At least in the US.
Using data from this Nielsen and Billboard report, Statista put together the following sales chart, broken down by genre:
Rock Tops The Charts In America
As you can see, rock music made up for almost 35% of total album sales in 2013. Hip-hop/Rap and Electronic trail far behind at 8.7% and 3% respectively. Is this surprising? How did your favorite genre rank? Let us know in the comments