A 33% "rate bubble" applied between $71,900 and $149,250 for married filing jointly, between $35,950 and $113,300 for married filing separately, between $43,150 and $89,560 for singles, and between $61,650 and $123,790 for heads of households, the purpose being to recapture the revenue that upper-income taxpayers had saved by applying the 15% rate."