A Brief History of Interest Rates July 27, 1998February 5, 2017 How long can these low interest rates last? I don’t know and I’m not making any predictions. But from 1880 to 1965, there was no such thing as a home mortgage for more than 6%, with bond rates even lower — and that was 85 years. (Some facts are so telling, I should just shut up and get out of their way.)