National results of the May 18 2011 local government election:

In the local government elections all voters cast two ballots: A Proportional Representation (PR) ballot, for a party, then a Ward ballot for the ward candidate in their area. Outside of the metros the voters cast a third ballot - for their local district council.

On the Ward ballot the African National Congress secured 8,143,397 votes (60.98 %) and on the PR ballot (62,93%) - an average of 61,95% for both (See Table 1). In the District Council elections the party received 5,455,411 votes (or 69,43%) of the total. Overall the ANC had 22,004,237 ballots cast in its favour (63.65%).

The Democratic Alliance received 3,177,883 (23,80%)on the Ward ballot and 3,216,006 (24,08%) on the PR ballot - an average of 23,94% for both. Because its support is concentrated in the metros it did less well in the District Councils, receiving 1,202,562 votes (15,3 %) on this ballot. Overall, the DA secured 1,202,562 votes on all three ballots (21,97%).

For analytical purposes the PR ballot is the best measure of a party's popular support. The Ward count is affected by the influence of the popularity of individual candidates and independents - a factor which does not apply in national or provincial elections. District Council votes are distorting because they give an additional 50% weighting to voters in rural areas.

If one compares the PR results between the 2006 and 2011 local government elections (see Table 2) the following emerges:

There were 3,505,412 more valid PR votes cast in 2011 than in 2006, a 35,58% increase. The ANC secured 1,936,009 more votes than last time, a 29.93% increase. Its share of the vote declined - from 65,67% to 62,93% - due to an even greater increase in the number of PR votes won by the DA.

The DA increased its number of PR votes from 1,608,154 to 3,216,006 - a 1,607,852 (99,8%) increase. As a result its share of the vote increased from 16,32% to 24,08%. However, it is important to remember that the DA had swallowed up the ID before this election, and the latter party did not contest the poll. The DA+ID received 1,825,915 PR votes in 2006 (18.53%). So the DA secured 1,390,091 more votes in 2011 than the two parties received separately last time - a 76.13% increase. And its share of the vote increased by 5.54 percentage points.

Mainly as a consequence of the National Freedom Party breakaway the IFP hemorrhaged support. It received 475,621 PR votes in 2011, 268,865 fewer than in 2006, a 36.11% fall. Its share of the vote dropped four percentage points to 3,56%.

Data source: www.elections.org.za.

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