Median rent and median renter income

Nationally, median rent is $920. In Philadelphia, median rent is $915, so it's pretty close. But! Gross median income for households that rent is $33,219 nationally, and only $26,624 in Philadelphia. So, the 41% I posted about the other day is way above average. 

Also worth noting that the recommended percentage of income to spend on rent is 30%, and I'm pretty sure that's supposed to be a percentage of net income, not the gross figures provided above.