Newzoo

The ranking is based on the number of unique sessions during a calendar month amongst the millions of game enthusiasts that use Overwolf’s in-game apps . The majority of the gamers that use software such as TeamSpeak and GameCapture are from the US and Europe so sessions outside of  those regions are discarded for this ranking. Overwolf supports most PC games

This table features the top 100 countries ranked on global game revenue estimates for 2017. These estimates are based on a combination of primary consumer research, transactional data, quarterly company reports and census data. The revenues are based on consumer revenues generated by companies in the global games industry and excludes hardware sales, tax, business-to-business services and online gambling and betting revenues.