My wife and I are both retired, She was a Government employee and receives a pension. I am 72 and she is over the FRA. What is the formula for determining her Spousal benefit? Do I subtract two thirds of her pension from my Social Security and she gets the balance, or is the formula different?
I'm assuming that your wife's government earnings were exempt from Social Security taxes and that she would therefore likely be subject to the Government Pension Offset (GPO). In that case, if your wife filed for spousal benefits on your record while you're living her benefit rate would be calculated by subtracting 2/3rds of her government pension amount from 50% of your primary insurance amount (PIA). Your PIA is the gross amount that you would now be receiving if you started receiving your Social Security retirement benefits at full retirement age (FRA). If the resulting amount would be zero or less, your wife would not be eligible to draw spousal benefits.
The same basic rule would apply to your wife's widow's benefits should you die before her, except in that case 2/3rds of her government pension amount would be subtracted from the full amount of your benefit instead of 50% of your PIA. So, depending on the amounts involved, it's possible that your wife may be eligible for some benefits as a widow even if she's not currently eligible to receive any spousal benefits.
For more information on GPO and it's exceptions, refer to the following Social Security publication: https://www.ssa.gov/pubs/EN-05-10007.pdf.