A leading indicator for the U.S. commercial real estate market continued decelerating for the fourth consecutive quarter on Wednesday, according to the National Association of Realtors, who also said that commercial real estate activity would weaken over the next six to nine months.

The NAR's Commercial Leading Indicator for Brokerage Activity moved down 0.9% in the second quarter, following a drop of 0.7% in Q1, pushing the index down to a reading of 117.9. The index is 2.1% lower than in the second quarter of 2007 when it stood at 120.5.

"The pace of decline has intensified due to job cuts and very sluggish economic activity since the beginning of the year, particularly in those industries requiring commercial building spaces," said Lawrence Yun, NAR's chief economist.

"We anticipate the weakest commercial brokerage activity in nearly three years as a result," he added.

The Commercial Leading Indicator for Brokerage Activity is an index that assesses market behavior in the major commercial real estate sectors. Using 13 variables, it was designed to provide early signals of turning points between expansions and slowdowns in commercial real estate.

The 13 variables are: industrial production, the real estate investment trust (REIT) price index, the National Council of Real Estate Investment Fiduciaries (NCREIF) total return, personal income minus transfer payments,jobs in financial activities, jobs in professional business service, jobs in temporary help, jobs in retail trade, jobs in wholesale trade, initial claims for unemployment insurance, manufacturers' durable goods shipment, wholesale merchant sales, and retail sales and food service.

By Patrick McGee and edited by Megan Ainscow