Bank Management Printers, Inc. produces luxury checkbooks with three checks and stubs per page. Each checkbook is designed for an individual customer and is ordered through the customer's bank. The company's operating budget for September 2022 included these data:
Number of checkbooks	15,000
Selling price per book	$20
Variable cost per book	$8
Fixed costs for the month	$145,000
The actual results for September 2022 were as follows:
Number of checkbooks produced and sold	12,000
Average selling price per book	$21
Variable cost per book	$7
Fixed costs for the month	$150,000
The executive vice president of the company observed that the operating income for September was much lower than anticipated, despite a higher-than-budgeted selling price and a lower-than-budgeted variable cost per unit. As the company's cost analysis expert, you have been asked to provide explanations for the disappointing September results.
Prepare both a static and a flexible budget based variance analysis of September performance. Bank Management develops its flexible budget on the basis of budgeted per-output-unit revenue and per-output-unit variable costs without detailed analysis of budgeted inputs.
What explains the disappointing September results? On which analysis do you base that conclusion (the static or flexible budget variance analysis) and why?