It's actually done way better than that, in rand terms it's done 200% in 5 years if you include divvies. I think your calculation didn't take into account the fact that the dollar strengthening against the rand also compounds. A better way to compare would be to compare both funds in Rand. The closest to that would be to compare STXIND and DBXWD over a 5 year period:
As you can see, DBXWD wins, most likely because the rand is a big loser. VWRD should have the same performace as DBXWD, but pay 0.43% more in dividends. VWRD pays about 2% per year after taxes, while STXIND pays 1.4% before taxes, so about 1.2% after. That means that even though VWRD has outperformed, it would also have paid about 0.8% a year more in dividends.
Plus of course, VWRD is VERY diversified, 6000+ companies, so a far lower risk than STXIND which has just 25 companies, but a huge 40%+ in two companies, SAB and NPN. With VWRD the biggest holding I believe is apple at 1.8%.
I've done a lot of research into the best play for a non-US resident to put their money, and the bight sparks at bogleheads suggest VWRD almost without fail. I'm going to transition all my holdings into it as soon as I can without incurring a huge amount of fees and taxes.
Edit, just thought I'd try a $ denominated graph. Here's VWRD compared to the iShares MSCI South Africa ETF, basically the SA all share index over the last 4 years (VWRD is only 4 years old):
How miserable does that make you, that in $ terms, the JSE has lost 20% over the last 4 years.
One more graph comparing VT, the world index US citizens can buy (lowest cost but foreigners mustn't buy it) to the JSE all share, all available data:
Here you can see that during the commodities boom, from 2009 to 2013, South Africa outperformed the world by a fairly long way. But in 2013 that ended, anyone want to place money on SA outperforming the world in dollar terms again anytime soon?