I have two children for whom I pay maintenance - my son aged 16 who shares his time 50/50 with myself and his mother, and my daughter aged 13 who lives solely with her mother.
Currently, the nominal 16% maintenance calculation of my gross taxable income is reduced because of the shared care of my son to 12% less a further discount of £7/week.
When my son leaves full time education he will drop out of the maintenance calculation and so I will then pay maintenance only for my daughter - at 12% of gross taxable income, with no deduction for shared care (so no additional £7/week deduction).
So bizarrely, the maintenance calculation for just my daughter is actually higher than for both my son and my daughter combined.
Only one of my children stays half their time at my house whilst the other one stays only with her mother. I still pay maintenance in respect of both children as that is what my ex- has claimed for, however it is discounted due to the shared care of my son - meaning that I have to house and feed him when he is with me and meet any other ‘day to day’ living costs, however I am not obliged to pay for stuff like his school trips, school shoes, winter coat, pocket money or any other expense not considered ‘day to day living costs’ (though I choose to give him some money).
Anyway, the basic rate maintenance for 1 child is 12% of gross income and for 2 children is 16%.
Shared care discount for one child only is half of half the total, I.e. 4% plus £7/week.
Hence total maintenance for both children (with one shared care) is actually lower than just for one child (with no shared care).