You can't really use 'non-smoking' in this context as really you are talking about a lack of action. If you were saying 21% of people account for the cigarette smoking in Japan , it works, as they are actually doing something. But to say 'non-smoking' doesn't really make sense...can you follow what I mean? If 5% of people get run over by a car every year you wouldn't say that 95% of the people acc