The concordance has been produced using employment information for males and females from the Census. The proportions in this concordance therefore apply to the distribution of employment, by sex. The concordance is based on the comparison of occupation data for one time period - August 1996. Use of the concordance to derive estimates for earlier periods assumes that the proportions derived in August 1996 will also apply to other time periods. However the relative contributions of particular occupations in the overall employment market change over time.
New occupations can emerge while others disappear.
Since the concordance is a snapshot, these changes are not reflected when the concordance is applied to other time periods. For this reason, applying a concordance may produce unlikely results for some occupations. Methodological differences between the Census and the LFS may also affect the applicability of the concordance to LFS data. The LFS is conducted by trained interviewers who are able to obtain detailed occupation information. Since the Census is filled in by respondents, there is little control over the type of occupation information provided.