Towards the end of last year, Statistics SA raised concerns about overreliance on single sources of information as a basis for economic and social measurement.
At the time, some prominence had been given to suggestions that Stats SA had been underestimating job creation. This was based largely on new registrations recorded by the unemployment insurance fund (UIF).
Yesterday's release of the September labour force survey (LFS) - the 12th round of this twice-yearly survey - demonstrates how important it is to have a long-term and consistent source of data, collected and analysed according to sound statistical principles.
The LFS is a twice-yearly household survey, specifically designed to measure the labour market. It provides insight into a variety of issues, including the level and pattern of unemployment, and the industrial and occupational structure of the economy.
The design of the questionnaire and definitions used conform to the requirements set by international bodies such as the International Labour Organisation.
The LFS collects detailed information of about 69 000 adults of working age (15 to 65 years) living in over 30 000 households across the country. These households, identified in each of the nine provinces, were visited by field staff employed and trained by Stats SA, and an LFS questionnaire was completed through face-to-face interviews for each household visited.
The LFS questionnaire collects very detailed information in a number of areas, thereby proving far more data than any single administrative source (such as UIF registrations) can supply. Eight sections, each focusing on a particular area of relevance, contain a total of 120 questions.
Household members running businesses.
The number employed - all persons aged 15 to 65 who did any work or who did not work but had a job or business in the seven days prior to the survey interview - was 12.
The number unemployed - persons aged 15 to 65 who did not have a job or business in the seven days prior to the survey interview but had looked for work or taken steps to start a business in the four weeks prior to the interview and were able to take up work within two weeks of the interview - was 4.
The labour force - the sum of employed and unemployed persons - was 16.
Those not in the labour force - those neither employed nor unemployed - were 12.
The population of working age - all persons aged 15 to 65 inclusive at the time of the survey - was 29.
Discouraged work-seekers - persons who want to work and are available to work but who say that they are not actively looking for work - 3.312 million.
The unemployment rate - the number of unemployed persons expressed as a percentage of the labour force - was 26.
The labour force participation rate - the number of persons in the labour force expressed as a percentage of the population aged 15 to 65 - was 56.
The labour absorption rate - the percentage of the population of working age who were employed - was 41.4 percent. The latest labour force survey allows for comparisons over five years (September 2001 to September 2005). It records changes in unemployment rates, job creation and job losses.
For example, the LFS reports that, in the year to September 2005, agricultural employment continued a downward trend. This was, however, more than offset by employment gains in trade (which increased by 482 000 jobs), finance (up 148 000) and construction (up 111 000). Over a longer period, from September 2001 to September 2005, 1.12 million jobs were gained in the labour market, of which 960 000 were in the non-agricultural formal sector.
This is the sort of authoritative detail that lies at the heart of official statistics, and which cannot easily be provided through irregular or inconsistent surveys, or through ad hoc analysis of single data sources.
Pali Lehohla is South Africa's statistician-general and head of Stats SA. For more information on Stats SA and its statistical output, including the latest LFS release, visit www.statssa.gov.