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How do I calculate back child support with interest in California when the monthly child support amount changes every month?

Berkeley, CA |

My ex-wife has not paid any child support since 2005 and now owes me about $15,000. Since her payments are reimbursements for tuition, medical expenses, etc. the amounts vary every month. I know that the interest rate in CA is 10% simple interest and the formula is "Interest = Rate x Principle x TIme", but is the time calculated monthly or yearly (60 months vs. 5 years) and do I have to do a separate calculation for every month since the principle varies?

I checked westlaw/CFLR and I don't think that an individual can purchase their products. Is this something I can do myself with a calculator and lots of time? I'm not in a position right now to pay a lawyer to do this for me.

Attorney Answers 1


  1. There is computer software that can help in this task, and yes the calculations are month-by-month. One program that does this is known as Executioner and is sold through westlaw/ California Family Law Reports.

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