Just the Beginning of a Long Stock Slide?

The slump in global stock prices could just be getting started as a few months of declines may not be enough to correct the years of booming stock prices, investment managers told CNBC.

"You had months and years on the upside and now you've got it on the down and people in a way just aren't used to it," Elissa Bayer, investment manager at Charles Stanley, said Tuesday.

"This is going to go on longer, the question is how long. You'd be very foolhardy to say how long that would be, but the fact is it did take years on the plus side," Bayer said.

The Dow Jones Industrial Average has lost about 10 percent since the start of the year, but gained over 16 percent between the start of 2005 and the start of 2007 alone.

"At the moment markets want to be bad and it's the financials leading the way … first of all it's perception and secondly, numbers coming through that is pulling the market down," Bayer said.

But stocks will eventually reach a level where investors will want to enter the market and buy, she said.

"There's a large cash over-hang, equity houses have a lot of money, eventually the banks will want to lend again," Bayer said. "Just at the moment I think that everyone is caught in the headlights and we have a lack of good news."