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At the beginning of the year, X Company expected to produce 3,100 units of its only product. Its estimate of fixed overhead was $10,000, and its estimate of variable overhead per unit was $6.82. At the end of the year, 2,900 units were actually produced, with actual total overhead cost of $30,399. 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]? \begin{tabular}{|r|r|r|r|r|} \hline \hline B: $727 & C: $850 & D: $995 & E: $1,164 & F: $1,362 \\ \hline \end{tabular}