Pascal receives a monthly allowence of $150. He saves an equal amount every month. He saves $432 in a year. What percentage of his allowence is saved every month?

Pascal saves $432 in a year, so he saves $432/12 = $<<432/12=36>>36 every month.

Thus, Pascal saves $36/$150 x 100% = 24% of his allowance every month. Answer: \boxed{24}.