Why the Burger Index Fell While Four Cities Rose

Burger Index, CostInflation’s fixed-serving grocery basket, fell about five cents on average across 12 tracked city areas from September 17 to 24. Four city baskets still rose. Jacksonville gained about 12 cents, the largest increase.

The split matters because the beef portion of the basket declined in every area. Yet a check of 560 beef item-by-area comparisons present on both dates found no change in those matched prices. The lower beef index reflected a changing mix of observed items, rather than a broad markdown on the same products.

The Burger Cost by City combines fixed amounts of raw beef, a bun, American cheese, produce, pickles and condiments into one grocery basket. The chart separates the beef component’s pull from the complete basket’s result.

One shared pull, different city totals

The 12-city basket mean moved from $5.36 to $5.31. Beef contributed an average 8.3-cent decline, with a negative contribution in every city. American cheese added about 2.4 cents to the mean basket, buns 1.3 cents and lettuce 1.0 cent. The smaller ingredients combined to reduce it by about one cent.

That left eight city baskets lower and four higher. Houston had the largest drop, about 22 cents; Clayton fell about 18 cents. Jacksonville rose about 12 cents, followed by East St. Louis at about eight cents. Philadelphia rose about three cents, and San Jose was nearly flat but slightly higher.

The beef index moved as the observed mix changed

For one pound of raw ground beef, the mean beef patty price index fell from $13.37 to $12.95 across the 12 areas. The burger basket applies a one-fifth-pound serving, turning that component move into the 8.3-cent downward pull.

The matched prices help explain the decline. Across the 12 city areas, all 560 beef item-by-area price comparisons present on both dates were unchanged. Seventeen entries left the observed set and 22 entered; the departing entries had higher average prices than the new entries in each area. The index declined as its observed product mix changed, without a broad price cut for unchanged beef items.

Jacksonville’s lettuce reading outweighed its beef decline

Jacksonville’s beef contribution fell about 3.1 cents and its bun contribution fell 5.5 cents. Its lettuce contribution rose about 19.5 cents, enough to lift the complete basket by about 12.5 cents.

The lettuce price history had 15 observed items in that city area on September 17 and 13 on September 24. The median price change among the 13 matched items was zero. The large lettuce-index move reflected both the observed basket mix and its price readings, rather than a 41% jump for the same lettuce item.

The next comparable weekly endpoint will show whether that city split lasts. The live Burger Cost by City index tracks each basket, while the beef and lettuce pages show the ingredients behind it.