The Boston office market has 1.5 million square feet of positive absorption year-to-date, the strongest performance since 2005, while suburban markets declined by 231,975 square feet during the same period.

Boston’s recovery continued in the third quarter with major leasing activity in the Downtown Crossing area. Tech companies Sonos and Carbonite, which leased 170,000 square feet and 52,000 square feet, respectively, highlighted the third-quarter activity, according to real estate brokerage Cassidy Turley’s Marketwatch report.

In the Financial District, four deals totaling more than 190,000 square feet were signed at 75 State St., and new inventory hit the market with the delivery of State Street Corp.’s 500,000-square-foot 1 Channel Center in the Seaport and Arnold Worldwide/Havas Media’s move into 125,000 square feet in the former Filene’s building.

Tight vacancies in Cambridge’s Kendall Square – currently 7.2 percent – have contributed to a 20 percent increase in rents in the last 12 months. But rents, now averaging $60.79 in East Cambridge, could be headed sharply higher in the next year with large tenants such as Amgen, Mass Innovation Labs and Baxter scouting space in the market.

The transformation of suburban office parks continues, as developers continue to add amenities such as retail and restaurants to attract office tenants. Shoe company Wolverine Worldwide committed as anchor tenant at Boston Properties’ 10 CityPoint in Waltham, which will contain a Posto pizzeria and Bonefish Grill restaurant, along with 230,000 square feet of office space.

But the suburban market felt the effects of several new availabilities, including 96,000 square feet of former TJX Cos.’ space at 500 Old Connecticut Path in Framingham.