Statistics Canada is out with a report of how the July jobs report was initially at +200 jobs then revised two weeks later to +42,000.
Statscan’s review of the issue reveals that the survey, which undergoes updates after every census, is in the midst of a redesign that occurs once per decade. As a result of changes being made, there was an unintended change in the way the system accounted for missing or incomplete data in its tabulations.
The survey usually accounts for holes in the data caused by non-responses by inserting plausible values where data are missing. Since many groups of respondents are the same from one month to another, there is usually some ability to check a new jobs report against the previous months and account for where data are missing.
Changes to files were made in the system that aggregates and disseminates data as part of the overall redesign in an effort to reduce errors. But since some of the changes were made as a maintenance activity, rather than a facet of the redesign, the testing process missed a step.
Short version: There was a hole on the spreadsheet that was supposed to be estimated but it was left blank.
