CPI...Consumer Price Index (1982-1984=100)?

Question

So I'm doing calculations for rent attempting to use the CPI. This is past rent. None of my calculations match with what is stated in th extensions, and Rent Increase letter. There's only one CPI for Wage Earners & Clerical Workers (US Average), all items, (1982-1984=100) that is updated each month, correct?

Answer 1

Almost. I believe there is a both a seasonally-adjusted and a non-seasonally adjusted index for "Wage Earners & Clerical Workers (US Average), all items (1982-1984=100)."

As you probably know, there are a whole bunch of different CPIs, but there are only two (seasonally-adjusted and not) that are exactly what you describe in your question:

Population Group: Urban wage earners & clerical workers

Area: US city average

Items: all items

Base period: 1982-84

It's possible that the disparity between your calculation and whoever's (a landlord's?) you're comparing it with is due to the seasonal variation. That should be fairly small, though, and - of course - it should really just affect the month-by-month changes within a year, rather than the year-to-year change.

It's also quite possible that you're using the correct index and the "other guy" isn't. Very often, even when a contract is very specific about exactly what CPI to use, people just ignore that and use whatever CPI is easiest to find. The other guy may, for example, be using all urban consumers, rather than wage earners and clerical workers.