Sales in South Africa, Lesotho, Botswana, Namibia and Swaziland fell to 1.3Mt from 1.4Mta earlier, the Johannesburg-based institute said.
Adjusting for the fact that August this year had one fewer sales day than the year-earlier month the decline would be 2.8 per cent, the institute said.
Sales in the region for January through August fell 2.9 per cent to 9.93Mt.
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