Tables of simple and compound interest [electronic resource] : Calculated to ascertain the amount and present worth at principal sums and annuities; with their comparative values, whether interest and annuities be payable yearly or half-yearly. With explanation and examples. To which are subjoined, a few remarks, in which Dr. Price's observations on reversionary payments, &c. &c. relative to the payment of the national debt, are clearly proven to be erroneous. By John Laurie, teacher of mathematics.