Vacancies at the largest US shopping centers reached a record 8.8% in the fourth quarter as unemployment rose and consumers spent less, research form Reis Inc said.

Vacancies at smaller neighbourhood and community centers increased to 10.6 %, the highest level since 1991, from 8.9% a year earlier.

'We expect economic pressures to continue to assail consumers and businesses,' Reis economist Ryan Severino said in the statement. 'Although it appears that we have reached the end of the technical recession, continuing high unemployment and inconsistent consumer spending patterns will weigh on retail properties for at least another 18 to 24 months.'