US natural gas futures decreased 1% on April 12–19, 2018. Prices decreased due to mild weather forecasts. The United States Natural Gas ETF (UNG) decreased ~0.5% on April 12–19, 2018, while the First Trust Natural Gas ETF (FCG) increased 4.5% during the same period. UNG seeks to track active natural gas futures. FCG seeks to track the performance of the ISE-Revere Natural GasTM Index.