Facebook is expected to post losses when it declares its first quarterly earnings this week since going public.

The technology giant’s disappointing performance follows on from one of the most closely watched initial public offerings of all time in May.

Since being launched, however, Facebook shares have fallen in value and closed on Friday at $28.76 (£22.38) – almost $10 below their initial price

Market observers are awaiting Thursday’s declaration with interest to see how investors feel about the stock since a mostly disappointing start.

More than half of the 36 financial analysts dealing with shares in the company do not rate Facebook as a ‘Buy’ – historically the threshold needed to encourage investors on Wall Street to part with their funds.

Shares in the company have repeatedly lost ground after investors questioned the company’s ability to rapidly increase its advertising revenue, particularly in relation to revenue from mobile phones.

Technical problems with its market debut on Nasdaq were also to blame for a disappointing start after the initial fanfare.

Facebook Inc. became the first American company to ever go public with a valuation of more than $100billion.

And the initial public offering made the company’s founder 29-year-old Mark Zuckerberg a fortune overnight.

But Michael Binger, a fund manager for Gradient Investments which owns stock in Facebook, says the real test is yet to come for the company.

‘If they miss, it would be catastrophic for the stock,’ he told Reuters.

‘This is a very important earnings quarter for them.

‘It will establish in people’s minds how they think of the company.’

Despite the jitters amongst some investors, however, there are also reasons for optimism.

The social media site still has over 900million users and has introduced a variety of new advertising features in a bid to beef up its revenue.

TBG Digital, which works with advertisers using the  site, showed that the cost of promoting products and services on Facebook has increased by almost 60 percent in the last year.

And the site’s ability to allow companies to specifically target their customers means that the site is likely to remain popular with advertisers.