Margins for high sulphur fuel oil (HSFO) extended declines for a second consecutive week in Asia, while very low sulphur fuel oil (VLSFO) was down for a third week, data showed on Friday. Prompt-month 380-cst HSFO/Brent crack (FO380BRTCKMc1) closed at a discount of 9 cents a barrel, versus premiums of above $2 in the previous …