To avoid this, in 1980 the US began to progressively increase social security contributions and raise the retirement age. Income above a certain threshold in addition to a pension may also be deducted.
所以一九八○年美國逐步修正為緩慢增加保費、延緩退休年齡，若退休金加上其他所得，超過一定門檻者，也會被扣稅。