The S&P/TSX Composite Index’s energy subgroup came under significant pressure in Friday trading, down more than five per cent as underlying energy prices fell.

The decline was far and away the largest drag on the overall index, taking 185 points off the table, as West Texas Intermediate oil prices fell below the US$80 per barrel mark for the first time since January.

Not a single constituent among the subgroup’s 38 members were in positive territory, with Birchcliff Energy Ltd, Spartan Delta Corp. and MEG Energy Corp. leading the declines, all down more than nine per cent as of 10:55 a.m. EDT.

The declines come as growth concerns and the stronger U.S. dollar put pressure on oil prices. The U.S. Federal Reserve has signalled it is willing to tolerate a recession if it means getting sky-high inflation under control, sending the U.S. dollar to a new record high, making commodities priced in greenbacks more expensive for investors.