Annual Figure For 1968 Is Based On Three Months (January- March). Source: 1947-1964, Business Statistics, The Biennial Supplement To The Survey Of Current Business, 1965; 1966 And Following; Survey Of Current Business, Current Issues.
This NBER data series q04194 appears on the NBER website in Chapter 4 at http://www.nber.org/databases/macrohistory/contents/chapter04.html.
NBER Indicator: q04194
Release: NBER Macrohistory Database
National Bureau of Economic Research, Consumer Price Index, Services, Total for United States [Q04194USQ350NNBR], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/Q04194USQ350NNBR/, November 29, 2015.