STAMFORD, CT—While leasing activity in both markets in the third quarter was significantly higher, the tale of the tape for New York City's northern suburbs—Westchester County, NY and Fairfield County, CT—was markedly different.

Third quarter leasing volume in Westchester County, driven in large part by the health care and legal sectors, rose nearly 52% in the third quarter as compared to the same period last year, according to a report by Cushman & Wakefield. Year-to-date office space demand was 17% higher than the five-year historical average, thus the positive market forces drove the county's overall vacancy rate down 340 basis points from the third quarter 2016 to the current 19.4% rate at the end of the third quarter 2017.

A total of 51% of the new lease transactions involved businesses in the health care or legal sectors. The largest deal in the third quarter was Montefiore Hospitals' renewal and expansion at South Westchester Executive Park in Yonkers for 281,497 square feet.