Note to users

The monthly gross domestic product (GDP) by industry data are chained volume estimates with 2002 as their reference year. This means that the estimates for each industry and aggregate are obtained from a chained volume index multiplied by the industry's value added in 2002. For the period 1997 to 2004, the monthly estimates are benchmarked to annually chained Fisher volume indexes of GDP obtained from the constant-price input-output tables.

For the period starting with January 2005, the estimates are derived by chaining a fixed-weight Laspeyres volume index to the prior period. The fixed weights are the industry output and input prices of 2004. This makes the monthly GDP by industry estimates more comparable with the expenditure-based GDP data, chained quarterly.

Revisions and conversion to NAICS 2002 and to reference year 2002

With the release, the monthly GDP by industry program uses the 2002 North American Industrial Classification System (NAICS) instead of NAICS 1997. In addition, the reference year for the chained dollar data and the base year for the constant price data have been changed from 1997 to 2002.

As a consequence, the CANSIM tables 379-0017 to 379-0022 are terminated and replaced with the new monthly table 379-0027. This new table includes changes to the industry detail, largely caused by the conversion to NAICS 2002, which principally affect sector 51 - Information and cultural industries.

The change in reference year and base year in new table 379-0027 changes the level but not the growth rates of the data for the period 1981 to 2001 inclusively, as it essentially consists of a rescaling of the already published data. However, the levels and growth rates for 2002 onward have undergone the regular monthly GDP annual revision process that incorporates the more recent input-output tables for 2003 and 2004, revisions to source data and to seasonal factors, as well as improvements to some of the methodologies used to derive monthly value added by industry.

To help users to convert from the terminated CANSIM tables to the new table 379-0027, a concordance (http://cansim2.statcan.gc.ca/cii/concordance/Monthly_GDP_NAICS_2002_industries.xls) between the old and new vector numbers is available. This document also provides a detailed list of the changes to the industry detail.

For more information, contact the dissemination agent (toll-free 1-800-887-4623; 613-951-4623; IAD-Info-DCI@statcan.gc.ca).