There are no really large companies in the Top 20 of Top Performers - they are mainly small-capitalisation companies with a smattering of medium caps in the form of Grindrod and HCI, both around R10bn.

This is a recurring theme in Top Performers. Large-cap companies find great difficulty in producing sustained robust earnings growth because their sheer physical size makes it difficult to keep growing from an already high base. Smaller companies, on the other hand, are able to grow strongly - both organically and through acquisition.

There are a couple of large-cap companies that may be able to penetrate the top echelons of Top Performers in the next few years, such as MTN and Sasol. Both have exceptional earnings growth prospects and both are in the top 10 by market cap on the JSE. Sasol, especially, looks like it will be able to profit considerably from the high oil price and the declining rand.

But generally, Top Performers should continue to be dominated by small and medium-cap companies. And by next year, quite a few of them could be coming from AltX, the JSE's small cap exchange. Once these new boys have established five-year listed track records, they will be eligible for inclusion. There have been some outstanding new listings on AltX, such as construction stocks WG Wearne and Esor.