I'm not sure how helpful knowing someone's income is when sampling user's from around the world unless you have some form of secondary data that helps place peo

I'm not sure how helpful knowing someone's income is when sampling user's from around the world unless you have some form of secondary data that helps place people on the same measuring stick That and comparing my salary to people in San Fransisco is depressing at face value (but less so when cost of living gets worked in)