Business ReportBEFORE THE BELL: Oil prices slide on solid inventory report; Canada March GDP report drops today SHARE ON: James Bowler, contributor, Thursday, May. 31st, 2018 Oil prices are slipping back as crude supply builds, and Canada is taking a hard hit in the energy sector.The price of oil pulled back this morning from its restarted rally after an inventory report surprised the market by showing crude supply was up. Oil prices have been volatile as analysts predict cuts in flow from Venezuela and Iran, but Canadian oil prices have been overly affected by Kinder Morgan pipeline and CP Rail uncertainty. Experts say the price of Canadian crude dropped more than 10 per cent this week. US crude is sliding to 67.77 a barrel this morning.Investors will get a look at Canada’s economy as the GDP report for March is being released today. Experts say this will give investors an indication of how likely a BoC rate hike in July is. Bank of Canada officials decided to keep the rate at 1.25 per cent yesterday, but hinted at the possibility of one or two more hikes coming this year.Ahead of the GDP report, the Loonie is up to 77.94 cents US.