Variable overhead efficiency variances are unfavorable when. The actual cost-driver activity is less than the standard activity allowed for the actual output the actual cost-driver activity exceeds the standard activity allowed for the static budget output the actual cost-driver activity is less than the standard activity allowed for the static budget output the actual cost-driver activity exceeds the standard activity allowed for the actual output Simmons Company has the following information available for variable overhead costs. Direct 17) Labor hours are the cost driver for variable overhead costs. At 60,000 machine hours, Korwall Company's static budget for variable overhead costs is $180,000. 1 At 60,000 machine hours, the company's static budget for fixed overhead costs is $300,000. Machine hours are the cost driver of all overhead costs. The static budget is based on 60,000 machine hours. At 60,000 machine hours, the company produces 40,000 units. The following data is available