I bought the TI Datamath calculator the week they went from [amt] to [amt]. It would add, subtract, multiply and divide. Gee... was that about 1972? Then, I bought the HP-80 financial calculator a couple of years later. It was a big box predecessor to the 12-C. I got reverse Polish notation and great support. I remember having it escape from my coat pocket and crash to the street when I jumped over the hedge by city hall (I have been a very active REALTOR.) HP replaced the case and made it work again at no charge! Then, along came the 12-C, the subject of these comments. WOW! What a machine. I have used it since it first came out, so with the Model 80 I have been using HP financial calculators for over 25 years. Now I have misplaced mine, so I just ordered a new one. Of course, that will insure I find the old one soon. But, having two is OK.