afraid i don't have any tech data,but i think it's more a case of what image the USA gives itself overseas(talking stereotypes via Hollywood here).
speaking as a Brit,we-maybe like other europeans-see how the US portrays itself & it's people through film in mixed ways ;powerful,great,welcoming,sinister,violent,creative,proud,scared,suspicious,friendly,hateful,freedom-loving,racist...etc.
hollywood is a business though,and as such,could not possibly be a responsible or credible conduit for truth or fair assessment due to it's need for using sensationalism to generate a profit. 



