The Consumer Price Index for Urban Wage Earners and Clerical Workers (CPI-W) increased 1.5 percent over the last 12 months to an index level of 250.112 (1982-84=100). For the month, the index was unchanged prior to seasonal adjustment.
CPI-W is the index that is used to calculate the Cost-Of-Living Adjustments (COLA). The calculation dates have changed over time (see Cost-of-Living Adjustments), but the current calculation uses the average CPI-W for the three months in Q3 (July, August, September) and compares to the average for the highest previous average of Q3 months. Note: this is not the headline CPI-U, and is not seasonally adjusted (NSA).
• In 2018, the Q3 average of CPI-W was 246.352.
The 2018 Q3 average was the highest Q3 average, so we only have to compare Q3 this year to last year.