Dynamic Mortality
U.S. Internal Revenue Service guidance specifies the mortality tables to be used for valuing Target Liabilities and for determining lump sums under the Pension Protection Act of 2006 (PPA). Certain tables permissible or required in the regulations are static tables, meaning that generational projection is not applied. These static tables are updated by the IRS annually to reflect mortality improvements.
Details of the methodologies are in the articles linked below: