the longest natgas chart i could find was 14 years, but i see the pattern. each cycle low is successively lower. the cycle highs are also successively lower. that suggests that there may be further downside. that would depress the share prices of the companies with natgas exposure. since gasx is a 3x bear of a basket of just such companies, its prospects for the near term look pretty good.
even if there is not much further downside in gas price, holding at low levels would depress the shares of those companies, which looks good for gasx near term.
https://markets.businessinsider.com/commodities/natural-gas-price
(link defaults to one year. hit max for longest)