Iron Mountain (NYSE:IRM) traded in the red Tuesday after warning investors that total revenue over the next two years might be lower than expected.

Fiscal 2010 revenue growth for the Boston, Massachusetts-based company is trending towards the lower end of its earlier guidance range of $3.12 billion and $3.16 billion, a reflection of continued soft core service activity levels, the company said in a statement.

According to that guidance, revenue for the year ended Dec. 31 would be 4% to 5% higher, respectively, than fiscal 2009.

Analysts polled by Thomson Reuters are on average looking for revenue of $3.15 billion.

The company expects fiscal earnings to be in the range of $1.07 to $1.16, or 10% to 20% higher than the earlier year.

In a preliminary forecast, the information management company said it expects fiscal 2011 results to fall short of expectations, anticipating per share earnings in the range of $1.17 and $1.26, on sales of $3.2 billion and $3.27 billion.

Analysts on average are anticipating $1.32 a share on revenue of $3.33 billion.

Meanwhile, the company announced Tuesday authorization by its board of directors to buy back an additional $200 million of its shares.

The authorization is in addition to the $150 million one announced earlier this year, of which $55 million remained as of Sept. 30.

The company’s chief executive Bob Brennan said the action demonstrates Iron Mountain’s “confidence in the long-term potential” of the company and its commitment to delivering “long-term value” to shareholders.

Stock will be repurchased from time to time in the open market or through negotiated transactions.

As of July 26, Iron Mountain had about 202 million shares outstanding.