The claim that 40% of the data used to calculate the CPI was guesstimated and that this is the highest ever in history is unverified because none of the reviewed authoritative sources provide evidence or official confirmation supporting this specific figure or historical comparison.
Unverified
40% of the data used to calculated CPI was guesstimated - the highest ever in history
CPI
Source: data.imf.org
At a glance
Verified October 26, 2025Key Evidence
The New York Times article explains methodological changes but does not confirm a 40% estimation rate.
Investopedia and official CPI data providers describe CPI calculation methods without quantifying estimation at this level.
Historical CPI datasets focus on inflation trends, not on the proportion of estimated versus observed data.
The reporting
What the Evidence Shows
The Consumer Price Index (CPI) is calculated using a combination of actual price data collected from various sources and statistical methods to estimate missing or unavailable data. While it is acknowledged that some estimation or imputation occurs in CPI calculations, especially when direct price observations are unavailable, none of the examined sources specify that as much as 40% of the data is guesstimated.
Furthermore, there is no indication in these sources that this proportion represents a historical high. The New York Times article discusses changes in CPI methodology over time but does not mention such a high level of estimation. Other sources like Investopedia and official datasets from the IMF and St.nytimes.comnytimes.comWhy Has the CPI Inflation Calculation Changed Over Time?
data.imf.orgdata.imf.orgCPI+1 more
Louis Fed describe CPI methodology and controversies but do not quantify the extent of estimated data at this scale. Historical CPI data sources focus on index values and inflation trends rather than data quality proportions. The claim appears to be either a misinterpretation or an unsupported assertion without publicly available evidence.fred.stlouisfed.orgfred.stlouisfed.orgConsumer Price Index for All Urban Consumers: All Items in U.S. City Average...
inflationdata.cominflationdata.comHistorical Consumer Price Index (CPI-U) Data+1 more
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