Please don’t forget about social security, that one year would make up the largest contribution of your social security benefits, and if you worked at least 10 more years after that, the AWI-adjusted Gross Income would drastically increase your Average Indexed Monthly Earnings (AIME). Anyway I don’t see why you wouldn’t use your savings from that first year to lawyer up a case for child support modification, there is no law that promises past earnings indicate future earnings.