If anyone had doubts about the strength of the rebound in South African stocks, the latest data on exchange-traded funds should put them to rest. Investors have cut their short positions in the largest ETF focused on the country to the lowest level since 2010, data from Markit show. That accompanied a surge in net capital inflows into 41 ETFs buying stocks in South Africa to a five-year high of $136-million in the first quarter, the data showed.The bullish sentiment is a turnaround from Reserve Bank figures released earlier this week that showed South Africans moved cash overseas for a 16th consecutive quarter in the final three months of 2015, the longest streak of quarterly outflows since the five years to end-September 1999."Investors are certainly coming back to SA," says Simon Colvin, a London-based research analyst at Markit. "The story there is one of commodity rebound and the bottom you have seen in the rand."The short interest as a proportion of outstanding shares in the $447-million iShares MSCI South Africa ETF traded at 2.4% this week, after falling as low as 0.9% on Friday.Investors are defying a second cut this year in the IMF's projection for SA's economic growth, rising borrowing costs, a slowdown in its biggest market, China, and political turmoil surrounding President Jacob Zuma. ..