An operational audit is being performed to evaluate the productivity of telephone sales representatives relative...

An operational audit is being performed to evaluate the productivity of telephone sales representatives relative to last year. The organization sells two similar products, one of which is priced 20% higher than the other. Prices did not change during the two years subject to the audit, and the gross profit percentage is the same for both products. The sales representatives are paid a base salary plus a commission.

Which one of the following items represents the best evidence that the organization’s sales representatives are more productive this year than last year?