A manufacturing company that has only one product has established the following standards for its variable manufacturing overhead. Variable manufacturing overhead standards are based on machine-hours.

Standard hours per unit of output5.20machine-hoursStandard variable overhead rate$11.65per machine-hour

The following data pertain to operations for the last month:

Actual hours8,700machine-hoursActual total variable manufacturing overhead cost$95,990Actual output1,600units

What is the variable overhead efficiency variance for the month?