Official statistics are published for different time periods, depending on the nature of the series involved.
Consumer and producer price indices, wholesale and retail trade, and manufacturing and mining production and sales, for example, are released every month. Gross domestic product (GDP) is estimated for every quarter, and for the year as a whole. The midyear population estimates are an annual series.
Earlier this week, labour market data were released for different time periods. The labour force survey, which is a six-monthly series although plans are afoot to increase its frequency to quarterly, reported that the official unemployment rate as at March was 25.6 percent, compared with 26.5 percent a year earlier.
The quarterly employment survey showed that the number of people employed in the formal non-agricultural sector increased by about 62 000 people, or 0.9 percent, from March to June this year. The survey also reported that gross earnings paid to employees during the quarter to June amounted to R165.35 billion. This represents a quarterly increase of R1.49 billion, or 0.9 percent, compared with the three months to March 2006.
Last week Statistics SA released one of its annual surveys, the economic activity survey (EAS), which was started in 1998. It derives economic measures based on information from the financial accounts of businesses. It is used to compile estimates of GDP and its components, provide economic indicator statistics, and provide information for the analysis of comparative business and industry performance.
The latest EAS, for 2005, contains estimates of financial data for nine industries: forestry and fishing; mining and quarrying; manufacturing; electricity, gas and water supply; trade; construction; transport, storage and communication; real estate and other business services (excluding financial intermediation and insurance, but including activities auxiliary to financial intermediation); and community, social and personal services (excluding government institutions).
Certain areas of economic activity are excluded: agriculture, hunting and related services; public administration and defence activities; education; financial intermediation; and insurance and pension funding.
Six new variables have been included in the latest EAS: salaries and wages; containers and packaging; property tax; losses from the redemption, liquidation or revaluation of liabilities; profit from redemption, liquidation or revaluation of liabilities; and profit from the sale or realisation for cash or revaluation of assets.
Seven extra financial ratios have been calculated. These are ratios between dividends paid and net profit after tax; turnover and inventories; net profit before tax and fixed assets; net profit after tax and fixed assets; company tax and net profit before tax; and capital expenditure on new and used assets and fixed assets.
The EAS reported that all industries reflected an increase in turnover between 2004 and 2005. The largest percentage increase of 14.2 percent was reported in construction, followed by mining and quarrying (9 percent), real estate and other business services (8.7 percent), trade (8.4 percent), transport, storage and communication (8.4 percent), electricity, gas and water supply (8 percent), manufacturing (5.1 percent), and community, social and personal services (3.3 percent).
Capital expenditure on new assets amounted to R144.34 billion in 2005, an increase of 3.7 percent from 2004. The largest increase was again reported in construction (79.5 percent), followed by electricity, gas and water supply (19.1 percent), mining and quarrying (8.8 percent), transport, storage and communication (5.1 percent), community, social and personal services (0.8 percent), and manufacturing (0.6 percent). The real estate and other business services and trade industries reported decreases of 14.1 percent and 1.7 percent, respectively.
Book value of fixed assets and intangible assets totalled R987.8 billion in 2005, an increase of 7.1 percent. The largest increase was again reported by construction (43.7 percent), followed by mining and quarrying (15.9 percent), electricity, gas and water supply (11.4 percent), manufacturing (5.5 percent), community, social and personal services (4.5 percent), transport, storage and communication (4.3 percent), and real estate and other business services (4.3 percent). The trade industry reported a decrease of 2.7 percent.
Closing value of inventories amounted to R251.48 billion in 2005, an increase of 12.8 percent.
Continuity is a central element of official statistics, as this allows for valid comparison to be undertaken for consistent time periods. However, revision and change is also required to take account of the changing structure of the economy.
This week saw the termination of a financial series recording remuneration of employees and turnover of institutions according to the regional services levies received by municipalities. The regional service council (RSC) levies were abolished with effect from July 1. This last release reports that R6.8 billion was collected from RSC levies in the calendar year 2005, R6.1 billion in 2004 and R5.5 billion in 2003.
From labour market statistics to data on economic activity, from financial indicators to consumer price indices, official statistics seek a balance between continuity and change in terms of what is measured as well as in the frequency in which data are gathered and published.