Quantifying data revisions using real-time data in South Africa

Griffin-Ellis, Ayrton and Horn, Aidan J. and Steenkamp, Daan (2026): Quantifying data revisions using real-time data in South Africa.

Abstract

Non-random revisions in macroeconomic statistics has important implications for forecasting and risk management and well as policy making. This policy paper evaluates the magnitude and historical dynamics of South African macroeconomic data revisions using a detailed true real-time dataset. We show that there is a lot of uncertainty around macroeconomic data in South Africa. In the case of GDP, estimates have tended to be revised upwards, by about 0.4 percentage point, on average. Investment, on the other hand, experienced larger revisions that GDP, with revisions tending to be negative. We show that the Reserve Bank's business cycle indicators have experienced the largest revisions of the series considered, raising concerns over their usefulness for nowcasting economic growth.

• Item Type: MPRA Paper
• Language: English
• Keywords: real-time data, vintages, data revisions
• Subjects: C - Mathematical and Quantitative Methods > C8 - Data Collection and Data Estimation Methodology ; Computer Programs > C81 - Methodology for Collecting, Estimating, and Organizing Microeconomic Data ; Data Access; E - Macroeconomics and Monetary Economics > E0 - General > E01 - Measurement and Data on National Income and Product Accounts and Wealth ; Environmental Accounts

References

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