As part of the annual audit of the books and records of a county, the State Auditor and Inspector shall make an audit of the expenditures of county sales tax revenue in order to determine whether the expenditures are being made according to law and constitutional provisions. The audit shall consist of a review of the ledgers and records of the expenditures of the sales tax proceeds. However, the annual audit required by this section shall only apply to any county sales tax revenue which is designated for a specific purpose as set forth in the ballot as passed by the voters of the county. The expense of the audit shall be paid by the county. The State Auditor and Inspector shall make a report of the audit and shall retain its report of the audit. The State Auditor and Inspector shall report any irregularities in the expenditure of sales tax proceeds to the Office of the Attorney General within thirty (30) days from the making of the report.