MB Real Estate's May 2009 market report shows that subleasespace is playing a large role in market troubles, having reached3.5 million square feet - a number predicted to grow further.Vacancy including sublease space is currently around 15.3%, rapidlyapproaching the 16.5% vacancy rate the market saw when the dot combubble burst around 2001. Meanwhile, Chicago's 12.2% vacancy rate,not including sublease space, has surpassed that of 2001, whenvacancy was 11.4%.

"As long as this economy continues, the sublease market is goingto continue to grow, evidenced by the unemployment rate and we'reat the start of seeing vacancy really shoot up," says AndyDavidson, EVP with MB. "Users' space needs are going to shrink, andgroups are going to be trying to renegotiate leases and givingspace back early, so you're going to see those numbers start takingeffect."

Davidson believes vacancy will increase for the next few years,citing the 11 million square feet delivered in the past decade,which saw negative absorption around 2001 and dramatic positiveabsorption in 2006 and 2007. "It's hard for me to look at theeconomy and say we're going to have numbers like 2006 or 2007 thatare going to turn this thing around in a V-shape," Davidsonsays.