I am not absolutely certain. the BlS would be the first choice.
I recommend tracking down papers from Dr. Milton Friedman. when I was in graduate school in economics (before biostatistics)
I recall we read several of his papers on monetary policy, IS/LM and inflation.. Its been a few years, I suspect his papers used and refernced historical information on inflation. I don't have a specific citation. This one looks promising and cites Friedman stating, "inflation is always and everywhere a monetary phenomenon"
https://anderseninstitute.org/friedmans-maxim-and-the-theory-and-history-of-inflation/
I don't have access to this 1992 book chapter by Friedman where he wrote about inflation
Friedman, Milton. Money Mischief: Episodes in Monetary History. New York: Harcourt Brace Jovanovich, 1992.
a large list of ctiations about inflation https://www.econlib.org/library/Enc/Inflation.html
and And with appropriate caveats to my recollection from graduate school in econonmics -before statistics were papers by Barro et al on "long term inflation"
this NBER paper by Barro seems to have some historical reports for inflation rates from 1960 onward
https://www.nber.org/system/files/working_papers/w5326/w5326.pdf
This paper suggests that BLS has only been tracking inflation since 1913
https://www.history.com/articles/inflation-prices-economy-wars-pandemic
Barro and Ursala wrote about macro economics crises and inflation since 1870
https://www.brookings.edu/wp-content/uploads/2008/03/2008a_bpea_barro.pdf
this has downloadable inflation data from 1913 onward
https://www.macrotrends.net/2497/historical-inflation-rate-by-year
https://www.macrotrends.net/2497/historical-inflation-rate-by-year#google_vignette
NOT -inflation but the Minneapolis Fed has the CPI from 1800 onward . They seem to be using the historical CPI to approximate the inflation rate
https://www.minneapolisfed.org/about-us/monetary-policy/inflation-calculator/consumer-price-index-1800-
I learned about inflation a long time ago and have forgotten a lot of that - and there may well be better sources to consider
-Chris
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Chris Barker, Ph.D.
Adjunct Professor of Biostatistics
University of Illinois Chicago, UIC-SPH
www.barkerstats.com---
"In composition you have all the time you want to decide what to say in 15 seconds, in improvisation you have 15 seconds."
-Steve Lacy
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