Ecopetrol S.A. (NYSE:EC) is included among the 10 Best Energy Stocks to Buy Under $20 According to Billionaires. With a workforce of over 18,000, Ecopetrol S.A. (NYSE:EC) is among the largest companies in Colombia and one of the leading integrated energy groups on the American continent. On May 6, the credit rating agency Moody’s downgraded […]