At the beginning of the year, X Company expected to produce 3,000 units of its only product. Its estimate of fixed overhead was $11,000, and its estimate of variable overhead per unit was $6.80.

At the end of the year, 2,600 units were actually produced, with actual total overhead cost of $30,483.

What was X Company's total overhead flexible budget variance for the year [a positive number means a favorable variance; a negative number means an unfavorable variance]?

A: $-591

B: $-739

C: $-923

D: $-1,154

E: $-1,442

F: $-1,803