What I'm saying is it doesn't state whether that is a 1 or 2 income family and the values of a 1 income family > 100k per year isn't the same as 2 incomes 50k+50k.

I think that has a bearing on the data in that if we were back in the day and only comparing apples to apples then 100k would be a 1 incoming family where the wife/mother does not provide that type of income.