The percentage is typically around 30% of gross for one child, but this can vary depending on income and other expenses paid for the child. There is a child support calculator on the Dept. of Revenue website. Separation/Custody Agreements typically provide for child support until age 23 if the child is in college full-time and living with the custodial parent.
However, if your income has decreased significantly since the last court order, then you can file for a modification to reduce your child support obligation going forward.
The language of your Separation or Parenting Agreement will dictate for how long you are ordered to pay support. If the agreement does not address it, the guidelines say for so long as the child is enrolled full time in college, yet living with the custodial parent during breaks, vacations, etc., you are required to continue support.
As Attorney Kell suggested, if your circumstances have changed in that you lost the overtime income, you may be able to file for a modification. Evaluate this possibility carefully, and with the advice of counsel, to make sure it is the most adventageous for you.
Christine DeBernardis, Esq.
This is not legal advice and is not intended to create an attorney-client relationship. You should speak to an attorney for further information.
With regard to the percentage of your pay that would go towards child support, you can determine what the guideline amount of the support should be through the child support guidelines worksheet.
That being said, where your child is over 18 years old, you may be able to make a case to deviate from the guideline support amount. Review Section 2F of the child support guidelines for dealing with children over 18 that are enrolled in college (where the court has the discretion in setting the child support amount in this type of situation).
I would suggest that you consult with an attorney before filing a modification since this is not a straight child support guidelines argument to reduce support.