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South Africa’s statistics agency will overhaul economic output data and revise the weights of the various sectors that are used to calculate gross domestic product.

The base year for measuring GDP will be updated to 2015 from 2010 from data to be released in September, the Pretoria-based Statistics South Africa said in an emailed response to questions. That means GDP figures from the second quarter of 2020 onwards will be calculated using the new reference year and revised weights.

Statistics South Africa usually rebases GDP data every five years and the last overhaul was in 2014. The adjustment is unlikely to bring material changes to recent growth outcomes in an economy that’s stuck in the longest downward cycle since 1945 and strained by political and policy instability, poor business confidence and regular electricity cuts.

South Africa’s GDP was 4.9 trillion rand ($338 billion) in 2018, according to the statistics agency’s data. While the National Treasury and central bank sees it expanding by 1.2% this year, international lenders such as the World Bank and International Monetary Fund forecast economic growth of below 1%.

To contact the reporter on this story: Prinesha Naidoo in Johannesburg at pnaidoo7@bloomberg.net

To contact the editors responsible for this story: Rene Vollgraaff at rvollgraaff@bloomberg.net, Gordon Bell

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