Welcome Corporation produces metal telephone poles. In the most recent month, the company budgeted production of 4,100 poles. Actual production was 4,400 poles. According to standards, each pole requires 7.0 machine-hours. The actual machine-hours for the month were 31,140 machine-hours. The standard variable manufacturing overhead rate is $2.50 per machine-hour. The actual variable manufacturing overhead cost for the month was $83,787. The variable overhead efficiency variance is: