The results are the first of the new Premier League season and follow from United's disappointing campaign last time out in which they failed to qualify for the lucrative UEFA Champions League under David Moyes.
Since then, the club have splashed the cash on a new-look side in an attempt to regain ground on their top-flight rivals.
However, United confirmed on Tuesday that overall revenue in the three months to the end of September had fallen from the 2014 figure of £98.5 million to £88.7m.
Commercial, broadcasting and matchday revenue all fell, based on the same time periods, while sponsorship revenue rose by 2.4 per cent to £46.3m, although this was offset by a reduction in tour revenue following United's close-season friendlies in America.
The club expect total revenue in the 2015 fiscal year to be between £385m and £395m, with the adjusted Earnings Before Interest, Taxes, Depreciation and Amortization (EBITDA) predicted to be between £90m and £95m.
However, a somewhat negative set of results was compounded by a small increase in gross debt - this figure rising by 0.3 per cent to £362.2m.
Executive vice chairman Ed Woodward - whose first season in the role coincided with Moyes' campaign - said the club's new deal with Chevrolet would lay the foundations for improved results in the remainder of the fiscal year.
"While we recognise that the 2014/15 fiscal year financial results will reflect our absence from the Champions League, we signed the largest kit sponsorship deal in the history of sport in the first quarter," he explained.
"And, with that concluded, we are excited to focus our efforts on the meaningful growth opportunities in sponsorship, digital media and retail and merchandising."
