However, output for Japan prior to 1970 and for the Netherlands prior to 1960 are indexes of industrial production. The national accounts measures for the United Kingdom are essentially identical to their indexes of industrial production. Comparable manufacturing output data are not available prior to 1977. The gross product originating series differs from the manufacturing output series that BLS publishes on quarterly measures of U.S. productivity and costs. The quarterly measures are on a sectoral output basis rather than a value added basis.
Sectoral output is gross output less intra-sector sales and transfers.
A value added concept has been used for the international comparisons series because the data are more readily available in the countries' national accounts, whereas sectoral output would require a complex estimation procedure. Measures of real output also may differ among countries because of different approaches to estimating the prices of high-technology products like computers and, in general, of products that undergo rapid quality change. The total hours measures are developed from statistics of manufacturing employment and average hours. Where such series are not available, the measures are developed by BLS using employment figures published with the national accounts, or other comprehensive employment series, and estimates of average annual hours worked. For the other countries, and the former West Germany before 1959, BLS constructs its own estimates of average hours.