Ohio Rev. Code Ann. § 5528.15

When the moneys to the credit of the highway improvement bond retirement fund, created by section 5528.12 of the Revised Code, are sufficient to meet in full all payments of interest, principal, and charges for the retirement of bonds and other obligations issued pursuant to Section 2g of Article VIII, Ohio Constitution, and sections 5528.10 and 5528.11 of the Revised Code, due and payable during the current calendar year, except the principal of notes which the commissioners of the sinking fund certify will be retired by the issuance of bonds or renewal notes, the commissioners of the sinking fund shall certify such fact to the treasurer of state.