Swifty Incasements manufactures protective cases for MP3 players. During November, the company's workers clocked 880 more direct labor hours than the flexible budget amount of 25,460 hours to complete 112,100 cases for the Christmas season. All workers were paid $8.59 per hour, which was $0.51 less than the standard wage rate. Calculate Swifty's direct labor efficiency variance. (If variance is zero, select "Not Applicable and enter for the amounts) $ Direct labor efficienty variance