Between May 15 and May 22, 2017, natural gas June futures fell 0.6%. During that same period, an equally weighted selection of natural gas–weighted stocks fell 1.5%.
On May 22, 2017, natural gas futures (UNG)(BOIL)(FCG) contracts for June 2017 delivery gained ~2.3% to close at $3.33 per MMBtu (million British thermal units).
The closer to the end user a function or firm is, the further downstream it is said to be. Raw material extraction or production are elements of the supply chain considered to be upstream.