My parents are divorced. What should I put as my "family's gross income" on the Common App?

Both parents will financially contribute to my education, and they had joint custody when I was < 18. Usually, college applications ask for your household income, and for that I’ve been putting my mother’s income (since I spend more time with her). But what should I put for family income? Any help will be appreciated.

I used my mothers only

The Common App isn’t what matters. It’s your CSS Profile that will determine how much FA you receive. The Common App info is used for analytical purposes only.