 Natures Sunshine Products NASDAQ:NATR saw a significant increase in short interest in the month of May. As of May 29th, there was short interest totalling 89,700 shares, an increase of 7.7 from the May 14th total of 83,300 shares. Based on an average daily volume of 33,500 shares, the days-to-cover ratio is presently 2.7 days. ... 