CMS wants to know my wife's income

Rod2

I have been given another income form to complete online, but it is asking about my wife's income.

Do I have to give it?

And can my Ex take child support from my wife’s income?

As a side note, I would have thought the CMS, part of the DWP already knows my wife's income from her national insurance records. So what is going on here?

Comms69

its not relevant to the calculation.

ZaSa1418

Nope do not give it to them , it is none of their business. How old is your child? 

Rod2

He is 10.  I see a lot of him, and it's been amicable, but I find is strange my ex wants to use CMS.  

By their arithmetic, the payments will be reduced, because its 15% for one child. and I'm paying £350 a month, which is about 30% of monthly net take home.

ZaSa1418

Definitely don't give your wife's income, its not relevant. 
What else is the form asking? 
Let her continue with it, she has cut her nose off to spite her face