Larry Summers highlights a paper from the NBER regarding measurement of CPI since the 1980s. Changes in how cost of housing is measured have lowered core CPI relative to the methodology used prior to the early 1980s (blue line below). Applying the current methodology (red line) retrospectively suggests that comparable core CPI is closer to the Volcker era.
“New paper shows past and present CPI inflation are more similar than official data suggests. When correcting for change in how housing inflation is measured, we find a return to target core inflation will require the same disinflation as achieved under Volcker.”