The "Accounts Receivable-Confirmation Statistics" working paper shown below was prepared by an audit assistant for the 2021 audit of Lewis County Water Company, Inc., a continuing audit client. The engagement supervisor is reviewing the working papers.

Required: Describe the deficiencies in the working paper that the engagement supervisor should discover. Assume that the accounts were selected for confirmation on the basis of a sample that was properly planned and documented on the working paper.

LEWIS COUNTY WATER CO., INC. Accounts Receivable-Confirmation Statistics 12/31/21 Tick Mark Legend = Agreed to accounts receivable subsidiary ledger. * = Agreed to general ledger and lead schedule. = Includes one related-party transaction. C = Confirmed without exception, W/P B-4. CX = Confirmed with exception, W/P B-5. Conclusion: The potential adjustment of $12,000, or 0.6%, is below the materiality threshold; therefore, the accounts receivable balance is fairly stated