Bill Bengen, creator of the "4% retirement withdrawal rule" in the US, stated that retirees' initial withdrawal rate should be raised from 4% to 5.5% under current, more realistic market conditions. Even in the most conservative scenario, he recommends increasing the withdrawal rate to 4.7%. Bengen, who proposed the 4% rule in 1994, said this adjustment reflects decades of research and an assessment of current markets, taking into account factors such as equity valuations and expected inflation.