The ZEMA graph above shows the North American natural gas spot prices on NYMEX for Henry Hub, Transco Zone 6, PG&E Citygate, and Chicago Citygates in February 2016. Units are in USD/MMBtu. While maintaining a consistent spread between different hubs (PG&E remained at the top and Henry Hub with Chicago at the bottom of the band) throughout the month, the overall prices slid down over the month period. Such an unseasonal price decline was due to the inventories remaining at the highest marks and also unseasonably warm weather.
February 2016 – North American Natural Gas Spot Prices (NYMEX)