Described as "one of the most challenging periods for revenue collection since 1994", 2009/10 is likely to rake in R68.9-billion less in tax revenue than the government initially expected, but R1.4-billion more than was projected in last October's Medium Term Budget Policy Statement.

In its budget policy document issued alongside the national budget Wednesday, the Treasury said tax revenue for the 2009 is estimated at R590.4-billion compared to the budgeted amount of R659.3-billion, a 5.5 percent drop from 2008/09.

It estimated total budget revenue for 2009/10 at R657.5-billion compared to a budgeted amount of R731.2-billion, a fall of 4.7 percent from the previous year.

The taxation drop came from falls in corporate tax (R29.5-billion), VAT (R22.3-billion), customs duties, personal income tax and secondary tax on companies.

For the 2010/11 year, tax revenue is estimated to rise to R647.8-billion with total budget revenue increasing to R738.4-billion.

As a percentage of GDP, tax revenue was estimated at 24.1 percent in 2009/10 and budget revenue at 26.8 percent. In 2010/11, these percentages are estimated at 24.0 percent and 27.3 percent respectively.

Mining royalties, which come into effect from 1 March are classified as a resource rent and fall into a non-tax revenue category.

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