They used combined incomes because BOTH parents are EQUALLY responsible for taking care of their children financially. In other words, if the state looks at both incomes and decides the NCP pay $400 a month in CS..what they're really saying is, based on both incomes the amount to raise the child(ren) monthly is $800 but the NCP pays half and the CP pays half, which the NCP's share would be $400. Actually I may be wrong..now that I think about it I think it's on a percentage. That's why if the CP isn't working, it shows the NCP's share is 100%. I guess determined by percentage of income. Anyway I can give you a site that might explain more about it.
As far as it based on gross, I have no idea, I think it's ridiculous too. The only thing I can think of is they are considering people getting their income tax money back. Which I think is wrong because #1 you don't get it all back #2 What if it's intercepted? #3 For NCP's who don't have joint custody, they don't even get to claim their children, yet if they are in the same household for 6 mo. out of the year they can, but I thought paying more support compenstated for that so what's the difference? (Besides the double taxation thing. Years should always be alternated in my opinion if both people are contributing to the support of the children) Hope that helps.
http://www.supportguidelines.com
