NEW YORK: AOL Chief Executive Tim Armstrong said investors will reap the benefit of an online advertising resurgence by 2011 if they hold on to the company's shares after it is spun out from Time Warner Inc later this year.

That will be a difficult sell to Time Warner shareholders looking at AOL's revenue trajectory over the last three quarters, which has seen steep declines of 20 percent.

Armstrong said it remains unclear when exactly the overall ad market will rebound, but he believes online video and display ads will see a resurgence in 18 to 24 months.