On January 1, your pension increases by a percentage that reflects the increase in the average of the Consumer Price Index for the previous 12-month period, calculated from October to September. This increase is known as indexing.
The indexing rate effective January 1, 2019, is 2.21%.
If you have been retired less than one full year on January 1, you get a fraction of the increase equal to the complete months you’ve been retired. For example, if you retired on September 20, 2018, your first increase, on January 1, 2019, would be 3/12 (October to December) of the total indexation percentage.