How often have you needed a TI-84 or similar scientific calculator post-grade school or college?

For me, we're talking post BS in Civil Engineering and I had the original scientific calculator; the HP-35. My Dad got it for me from his "Jewish Connection" for 1/2 price which was still $200 in my junior year. Quite a change from using a side rule (slip stick). It had the functions engineers used to calculate loads, stresses, pressures, ... you name it. It served me well during 3 deployments to Antarctica where I was doing ice strength calculations along with more simple functions for explosives work. I used it in '81 to take my PE exam, which at the time was a two day affair as, besides Civil, I had to do Seismic and Surveying elements. Funny thing, the display died just after I did the final check on my final answer for that exam. My wife was more than bemused as I conducted a funeral service and buried it in the back yard. Today's much cheaper and powerful units have the entire programming so you just have to enter the up front parameters and it spits out the answers. I still use a HP-11C for occasional calcs. I believe that's a long discontinued one as well.

LOL I bought a basic calculate that could add, subtract, multiply, and divide for $69. Today they give them away if they can get anyone to take one.

Don't need one to work on an old tractor.