The company is at risk of cutting its dividend.United Parcel Services (UPS -2.72%) has been getting a lot of attention as one of the three highest-yielding stocks in the S&P 500 (^GSPC -2.71%) along with chemical giant LyondellBasell Industries and consumer packaged food company Conagra Brands. But the yields of these companies have been going up because of falling stock prices.UPS' dividend yield is hovering around an all-time high of 7.6%, as the stock price is down 31.3% year to date and 47.7% in three y ...