You are auditing a large publically traded client. In testing the internal control that all invoices have been shipped, you have decided that the tolerable deviation rate will be 2%. The confidence level for this test is set at 97.5% and based on last years audit, two errors could be present in the population.

To perform this test you are examining a file of sales invoices with attached shipping documents. The shipping document numbers range from 12,624 to 35,173 and the sales invoices range from 17,283 to 39,682. The following table below is provided for you.

	Confidence Factor
Number of Expected Errors	Acceptable Risk of Incorrect Acceptance
1%	2.5%	5%	10%
0	4.51	3.69	3.00	2.31
1	6.64	5.58	4.75	3.89
2	8.41	7.23	6.30	5.33
3	10.05	8.77	7.76	6.6

What is the required sample size?