64 Pa. Stat. § 532
From and after the passage of this act, it shall be the duty of the surveyor general, on the settlement of any account for moneys due the commonwealth on lands which may have been surveyed, on proprietary office rights, or warrants issued by this commonwealth, or on actual settlement and improvement, to charge the following rates of interest, namely: On all lands where the original purchase money is twenty pounds, (fifty-three dollars and thirty-three and one-third cents,) per hundred acres, one per cent. per annum; on lands issued at the rate of fifteen pounds ten shillings, (forty-one dollars and thirty-three and one-third cents,) two per cent. per annum; on lands issued at the rate of ten pounds, (twenty-six dollars sixty-six and two-third cents,) and nine pounds, (twenty-four dollars,) three per cent. per annum; on lands issued at the rate of five pounds sterling, (twenty-two dollars and twenty-two and one-fourth cents,) and that issued at the rate of twenty dollars, three and one-half per cent. per annum; on land issued at the rate of five pounds, (thirteen dollars and thirty-three and one-third cents,) four per cent. per annum; on lands issued at the rate of fifty shillings, (six dollars and sixty-six and two-third cents), six per cent. per annum; no interest to be charged on lands issued at eighty cents per acre: Provided, That in no case, either of warrant, location or improvement, or any other office right, shall interest be charged on the purchase money of any of the aforesaid lands, for the time which elapsed between the second day of December, 1776, and the second day of December, 1783: Provided further, That no interest be charged on any lands north and west of the rivers Ohio, Allegheny and Conewango creek, previous to the third day of April, 1797, and in all cases where patents are issued upon the actual settlement and improvement, to any actual settler, no interest shall be charged for five years after such improvement and settlement was commenced: Provided nevertheless, That the owner of any unpatented tract of land, who is actually occupying same, shall have the benefit of the act, passed April 10, 1835, entitled "An act to graduate lands on which money is due and unpaid to the commonwealth of Pennsylvania," and the supplement thereto, passed May 4, 1855, until the first day of December, 1859, and this proviso shall also extend and apply to laws embraced in the second section of this act.
64 P.S. § 532