SUBSCRIBER NOTE: Platts proposes to change US NGL assessment roll timing November 1

S&P Global Platts is proposing to change the roll timing for US natural gas liquids assessments, except for natural gasoline, with effect from November 1, based on market feedback and observed trading liquidity.

Platts understands that trading activity in these markets typically remains focused on prompt-month barrels through the end of the month.

For example, Platts observed that between April 1 and July 31, 2019, more than 80% of barrels traded in these markets on the last day of each month were for delivery in the prompt month.

Under the proposed change, the assessments would reflect trading in barrels for delivery any day in the specified month -- also known as "any" barrels -- through the end of the month.

Currently, the assessments reflect trading in barrels for delivery any day in the specified month, up to three days prior to the end of the month, following which the assessments roll over to the next forward month.

For example, under the proposed change, Platts will be assessing November (M1) and December (M2) barrels between November 1 and November 30, and this will roll over to December (M1) and January (M2) barrels on December 1.

Platts publishes assessments for the prompt month and the next forward month for all Mont Belvieu NGLs, except for isobutane.

This proposed change would affect the following assessments:

Assessment Name Code Non-LST Mt Belvieu cents/gal: Ethane/propane mix M1 PMUDA05 Ethane/propane mix M2 AAWUB00 Ethane purity M1 PMUDB05 Ethane purity M2 AAWUC00 Propane M1 PMAAY00 Propane M2 AAWUD00 Normal butane M1 PMAAI00 Normal butane M2 AAWUF00

Conway, Kansas: Ethane/propane mix PMAAO00 Propane PMAAT00 Normal butane PMAAD00 Isobutane PMAAA00

Bushton, Kansas: Propane AALBE00

Hattiesburg, Mississippi: Propane AALBC00

Non-LST Mt Belvieu $/mt: Isobutane PMAAB00 Propane AAXDD00 Normal butane AAXDC00

Please send all feedback and questions by September 20 to oilgroup@spglobal.com and pricegroup@spglobal.com.

For written comments, please provide a clear indication if comments are not intended for publication by Platts for public viewing. Platts will consider all comments received and will make comments not marked as confidential available upon request.