I’ve repeatedly claimed that public schools are alone in having suffered a productivity collapse over the past 40 years: their outcomes stagnating or even declining while per pupil costs have skyrocketed. Is that really true?

Dr. Stephen Bohrer, who appears to work in Colorado’s public school system, begs to differ. Responding to a recent op-ed of mine, he writes that: “The price of a Baby Ruth is up 2,000% since 1970. It doesn’t taste any better and is smaller.”

Though historical prices on Baby Ruths are hard to find, there’s a nice suite of data on the Hershey bar, which seems a fair enough test of the good Dr.‘s claim. According to FoodTimeline, the price of a 1.375 oz Hershey bar in 1970 was 10 c, and the price of a 1.55 oz bar in 2008 was 59 c. Adjusting the first price to 2008 dollars puts it at 55.5 c.

So the real price-per-oz of a Hershey bar FELL from 40.4 c to 38.1 c over the past 40 years. And it didn’t get any smaller. No gold star for Dr. Bohrer.

So, who else wants to play Stump the Chump? If you think you know a field that has suffered a productivity collapse like education over the past 40 years, send me an e‑mail with your claim and the data on which it’s based (ACoulson |at| cato​.org). If anybody comes up with a winner, I’ll report it here.