Postal delivery company FedEx said the climbing oil price and a strong dollar contributed to a $895m (£570.2m, €797m) loss in its fourth quarter to 31 May.

The company failed to deliver in its fourth quarter and full year results published on 17 June.

Frederick W Smith, the 70-year-old founder, CEO, chairman and president of the company, said in a press release: "Fiscal 2015 was a transformative year for FedEx with outstanding financial results driving expanded long-term value for shareowners ... I am very proud of the FedEx team for its accomplishments and look forward to a successful fiscal 2016."

The company took out $4.88 per share in costs to cover changes in pensions and $0.62 to cover damages to its aircrafts.

FedEx said it expects "continued moderate economic growth" for the 2016 fiscal year and said it will focus on initiatives to improve profit.

The delivery company announced that it would raise the mandatory retirement age for directors in the company's guidelines from 72 to 75. The company said this is consistent with a market trend but it is also convenient for FedEx as its chairman and president is turning 71 in August.