Preble Company manufactures one product. Its variable manufacturing overhead is applied to production based on direct labor$-$hours and its standard cost card per unit is as follows:

Direct materials: $4$ pounds at $$9$ per pound $ $36$

Direct labor: $3$ hours at $$15$ per hour $45$

Variable overhead: $3$ hours at $$6$ per hour $18$

Total standard cost per unit $ $99$

The planning budget for March was based on producing and selling $26,000$ units. However, during March the company actually produced and sold $31,000$ units and incurred the following costs:

Purchased $155,000$ pounds of raw materials at a cost of $$7\mathrm{.}20$ per pound. All of this material was used in production.

Direct laborers worked $56,000$ hours at a rate of $$16$ per hour.

Total variable manufacturing overhead for the month was $$524,720.$

$14.$ What is the variable overhead rate variance for March?