Comment by jldugger

Well, the $5.14 figure is using the generalized inflation number derived by tracking the price of a specific basket of goods over time, across the entire country. This is a reasonable number to pick.

If you narrow down to Food for all Urban Consumers[1], it shifts to more like $5.24. If you look at "Food away from home in New York-Newark-Jersey City, NY-NJ-PA, urban wage earners and clerical workers, not seasonally adjusted" that number moves to $7.60. Which confirms your intuition: restaurant prices are way higher than the overall inflation rate predicts.

How do we explain the difference? A variety of ways. Maybe the burgers you get are "better" in some way. Bigger. Better cut of meat. More veggies and toppings. I wasn't around in 1959 and never ate at that specific diner, but it's a real possibility. In fact, this is explicitly called out in the FAQ[3]:

> Specifically, in constructing the "headline" CPI-U and CPI-W, the BLS is not assuming that consumers substitute hamburgers for steak. Substitution is only assumed to occur within basic CPI index categories, such as among types of ground beef in Chicago. Hamburger and steak are in different CPI item categories, so no substitution between them is built into the CPI-U or CPI-W.

There's also some other complicating factors to account for, like coupons and bundling. Like consider Applebee's Really Big Meal Deal deal. "NEW Big Bangin’ Burger with unlimited fries & soda, still just $9.99" Or you can order just the burger for... $15.99[4]. I don't even know how BLS copes with that and am sorta guessing they just take the a la carte prices for consistency, even though that likely overstates price levels consumers actually pay?

[1]: https://data.bls.gov/dataViewer/view;jsessionid=3A241A4C4F0A... [2]: CWURS12ASEFV [3]: https://www.bls.gov/cpi/factsheets/common-misconceptions-abo... [4]: https://www.applebees.com/en/menu/handcrafted-burgers/big-ba...