May 4 (Reuters) - U.S. refiner HollyFrontier Corp reported a 91 percent fall in quarterly profit hurt by a steep fall in refining margins and lower refinery utilization rate amid a rise in diesel and gasoline inventories.
U.S. refiners voluntarily reduced output in the first quarter after ramping up production last year to benefit from weak prices of their main feedstock - crude oil.
Crack spreads, the difference between the prices of crude oil and refined products, have narrowed sharply due to a spike in distillate and gasoline inventories in the United States.
Average sales price per produced barrel fell to $46.44 from $69.61 a year earlier, pressuring refinery gross margin, which fell to $7.59 per produced barrel from $16.69.
However, Chief Executive George Damiris said he expects gasoline margins to continue to strengthen in the current quarter.
HollyFrontier's refinery utilization rate fell to 88.3 percent in the first quarter ended March 31 from 94 percent a year earlier.
The net profit attributable to the company's shareholders fell to $21.3 million, or 12 cents per share, in the quarter, from $226.9 million, or $1.16 per share, a year earlier.
Sales and other revenue fell 33 percent to $2.02 billion. (Reporting by Amrutha Gayathri in Bengaluru; Editing by Shounak Dasgupta)