In September, Numbers Incorporated sold 40,000 units of its only product for $339,000, and incurred a total cost of $315,000, of which $34,000 was fixed costs. The flexible budget for September showed total sales of $390,000. Among variances of the period were: total variable cost flexible-budget variance, $7,000U; total flexible-budget variance, $81,000U; and, sales volume variance, in terms of contribution margin, $36,000U.

The amount of operating income in the flexible budget (FB) for September was: