For helpful comments and suggestions, we thank Zarek Brot, Tatyana Deryugina, Amy Finkelstein, Jon Gruber, Yunan Ji, Timothy Layton, Barry Nalebuff, Julian Reif, Molly Schnell, and Mark Shepard. The Medicare data used in this paper were acquired and maintained with support from the National Institute on Aging (R01AG075073) and the National Science Foundation (Award 2049250). The authors have no conflicts of interest to disclose.