53 Pa. C.S. § 8122
(a) General rule.--No local government unit shall authorize or issue tax anticipation notes in any one fiscal year which in the aggregate shall exceed 85% of:
(1) In the case of notes solely payable from and secured by a pledge of taxes, the amount of the taxes levied for the current fiscal year.
(2) In the case of notes solely payable from and secured by a pledge of revenues other than tax revenues, the amount of the revenues pledged.
(3) In the case of notes payable from and secured by a pledge of taxes and other revenues, the sum of the taxes levied and the revenues pledged.
The taxes or revenues or both shall be certified, pursuant to section 8126 (relating to certification as to taxes and revenues to be collected), as remaining to be collected or received in the fiscal year during the period when the notes will be outstanding. The certificate shall be as of a date not more than 30 days prior to, and no later than, the date of the vote on the resolution authorizing the issue and sale of the tax anticipation notes.
(b) Computation of notes outstanding.--In computing the aggregate amount of tax anticipation notes outstanding at any given time during the fiscal year for the purpose of the limitation imposed by this section, allowance shall be made for notes that have already been fully paid and for amounts already paid into appropriate sinking funds, if any.
53 Pa.C.S. § 8122