A 27% slump in cargo shipped to the ports of Los Angeles and Long Beach in Southern California over the past year has led to unprecedented declines in demand for local logistics real estate, according to a new report from Prologis. It is unclear how much of those shipments can be recaptured. 

Prologis attributes the ports' current slump to a decline in overall global activity, as well as diversions of cargo to other U.S. ports caused by a year-long dispute with the International Longshore & Warehouse Union (ILWU) over terms of a new labor contract. 

Amid disruptions to port operations caused, workers said, by labor shortages but employers claimed were due to intentional labor actions, a number of shippers and importers diverted cargo to other U.S. ports, especially on the East and Gulf Coasts.