Hello Larry I think you or your softwares
You know
Duke working and start his social security
Age 64 his benefits month 1500 dollar
he worked more than social security limit
So social security with hold dollar social security withholds duke money during work period 20,000
So duke reach full retirement age 66
How to calculate social security
And added his benefits
Write me as my answer
Thanking you

Hi. For each month that Duke's Social Security retirement benefits are withheld due to the earnings test, 5/9ths of 1% of his primary insurance amount (PIA) would be added back to his benefit rate when he reaches full retirement age (FRA).

For example, let's say Duke's PIA is $1800, which is the benefit rate he'd have received if he had started drawing his benefits at his FRA of 66. However, Duke's benefit rate is reduced for age to $1560 because he started his benefits when he turned age 64. Duke continues working after claiming his benefits, and due to his earnings 6 months of his benefits are withheld between ages 64 and 66. As a result, when Duke reaches FRA, $60 (i.e. 5/9ths of 1% x $1800 x 6 months) would be added back to his benefit rate. That would increase Duke's benefit rate from $1560 to $1620.

Best, Jerry