AVF Company processes an average of 400 vouchers payable every month. Each voucher package contains a copy of the check disbursed and supporting documents such as vendor invoices, receiving reports, and purchase orders. The internal auditor plans to examine a sample of vouchers listed in the voucher register using attribute sampling to evaluate the effectiveness of several controls. The attributes of interest include:
■ Agreement of voucher amounts with invoice amounts.
■ Voucher canceled after payment. Based on experience, the auditor expects a deviation rate of 2 percent for the first attribute and 1 percent for the second. He decides on a tolerable deviation rate of 7 percent for the first attribute and 6 percent for the second. He sets the risk of assessing control risk too low at 5 percent. Assume that the auditor’s tests uncovered two occurrences of voucher amounts not agreeing with invoice amounts and two occurrences of vouchers not being canceled after payment.
a. Complete the following schedule. (Note: round sample size per table up to next number ending in zero for sample size used.)

b. Evaluate the sample results for the two attributes. Your answer should include:
■ A statistical conclusion for each attribute.
■ The audit decision you would make based on the quantitative sample results for each attribute.

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Risk of assessing control risk too low Tolerable deviation rate Expected population deviation rate Sample size per table Sample size used Number of deviations identified Sample deviation rate Achieved upper deviation limit Attribute 1 Attribute 2