Key Energy Services’ (KEG) year-to-date returns as of May 11 were 45.6%. In comparison, the Energy Select Sector SPDR ETF (XLE) has risen 6.2% in the same period. XLE tracks an index of US energy companies in the S&P 500 index. The VanEck Vectors Oil Services ETF (OIH) has had year-to-date returns of 7.6%. OIH tracks an index of 25 OFS (oilfield equipment and services) companies.