Joseph McKenna, Union Steamboat Company v. Erie Western Transportation Company…
“ The people of the state of Michigan enact: That the interest of money shall be at the rate of $5 upon $100 for a year, and at the same rate for a greater or less sum, and for a longer or shorter time, except that in all cases it shall be lawful for the parties to stipulate in writing for the payment of any rate of interest not exceeding 7 per cent per annum: Provided, That this act shall not apply to existing contracts, whether the same be either due, not due, or part due.'According to its title the act is one to regulate the interest of money on account and interest on money judgments. ”
