Smaller cities (Size B/C): inflation calculator and CPI-U since 1996

Is your town in Size B/C?

Probably, if it is urban and not one of the 23 metros on the CPI by city list. The BLS Handbook defines two kinds of areas in the sample. A metropolitan area has an urban core of more than 50,000 people; a micropolitan area has a core of 10,000 to 50,000 (BLS Handbook, design). Areas above 2.5 million are self-representing and form Size Class A. All the others, metropolitan and micropolitan, form Size Class B/C. The Handbook counts 52 such non-self-representing areas in the 2018 sample and says they represent about 58 percent of the CPI-U population. In the Handbook's words, such areas represent "not only themselves, but other areas in their region and size class", and none of them has a published index of its own.

Some places sit outside the CPI-U population altogether: the BLS FAQ lists rural nonmetropolitan areas, farm households, military installations and institutions. No BLS index measures them directly, and Size B/C is only the nearest stand-in.

Size B/C or your region?

Both are published every month and both are built for places without their own index. The region keeps geography: a small city in the South moves with the South. Size B/C keeps scale: it groups smaller places across the whole country. The BLS FAQ urges users "to consider adopting the national or regional CPIs for use in escalator clauses", so for a contract the regional index follows that advice most closely. Size B/C is useful when the question is about smaller places as such, or when you want a check on what the regional figure says. The BLS also publishes cross-classifications of region and size class; this site does not carry them.

How smaller places have moved

Over the latest 12 months, Size B/C ran ahead of the big metros. Shelter moved +3.4 % against +3.0 % in Size A, energy +21.1 % against +19.5 %, and food at home +1.3 % against +2.5 %. Group series for Size B/C start in December 1997, a year after the all items index.

On annual averages since 1998, smaller areas had the faster year in 7 of 28 years. Their fastest year was 2022, at 8.2 %; their slowest 2009, at -0.4 %.

Reading the base, and October 2025

The base is December 1996=100, so the level for September 2026 is 205.65, far below the national level on 1982-84. Work with percent changes when you compare. October 2025 has no value here either, after the lapse in appropriations, and the 2025 annual average rests on 11 months; the October 2025 page has the rest.