SUBSCRIBER NOTE: Platts decides to change Algonquin city-gate natural gas methodology

S&P Global Platts has decided to change the methodology for the Algonquin city-gate natural gas daily and monthly index effective trade date July 1 for the daily market and August bidweek for the monthly market.

Due to constraints at the Cromwell compressor station, Platts has observed a price divergence when looking at trading activity south (upstream) of the compressor station. These trades currently fit methodology but tend to diverge from other reported transactions on a given day depending on the volume associated with these trades. Following a period of market consultation and subsequent proposal note published on May 3, 2021, which can be found here;, where Platts proposed to not include trades done south of the Cromwell compressor station. Only trading north (downstream) of the compressor station will be included in the location. New Methodology: Deliveries from Algonquin Gas Transmission to all distributors and end-use facilities in Connecticut, Massachusetts, and Rhode Island. Trades done upstream of the Cromwell Compressor station are not included.

The methodology change will affect the indices published on NG1301 and NG1309 and in the Gas Daily and Inside FERC First of the month publications. The assessment is databased under the following codes: IGBEE00(daily) and IGBEE03(monthly).

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