Average asking rents for class A offices are now $30 per sf, while class B averages $23 per sf and laboratory space is $46 per sf with sublease rents usually 25% to 50% less. These figures have remained virtually unchanged for the last three quarters.

According to Daniel Sullivan, a Cresa Partners vice president, office rents for class A space will likely drop because most Cambridge property owners, who were hoping for a fast market recovery, are now resigned to a very slow process. "It's now more cost effective for landlords to discount their space and retain tenants than it is to lose those tenants and carry the vacant space as a liability," he says, adding that many companies in Cambridge will likely find flat rents in "class B+ or A-", quality buildings that may offer fewer amenities.

The report demonstrates that sublease office inventory continues to decrease, with property owners taking back the space at a moderate rate. But with such a great surplus of space on the market, Cresa Partners says it does not expect rents to start rising for at least another year, or until the overall vacancy level goes below 15%.