The GATT rate is the negotiated tariff level for international trade agreements.
The PBGC rate refers to the insurance premium rate set by the Pension Benefit Guaranty Corporation to protect pension benefits.
*Note regarding ERISA 4022 immediate and deferred lump sum interest rates - On September 9, 2020, PBGC issued a final rule providing that, starting in 2021 PBGC will use rates published by IRS [i.e., the IRC 417(e)(3) rates] to determine lump sum amounts for plans terminating after 2020. Because of that change, the December 2020 immediate and deferred rates shown in the November 2020 Monthly Interest Rate Summary were the last “legacy” 4022 rates that will be published. The final rule contains a table that enables practitioners to determine immediate and deferred interest rates in accordance with PBGC’s historical methodology for months after December 2020. Individuals seeking information about the interest rates their plans use to determine lump sums should contact their plan directly.