well sir, I had fun with tests back then; aced the "junior english exam", to screen out engineers y'know, and then the AFOQT (air force ofcr qual test), then the eit, and the pe -- and became a manager with a conscience, which was an un-needed trait (much of the time) -- then, after I retired at 59.75, the $$ were too much, as you say. it was for job security, anyway, and I no longer needed a job. so, 'bye! coincided with the immaculation, almost. OK; 'bye! -- j

retired, now, after spending 33 years on the active list in Tennessee -- the folks at work didn't call me back as a consultant, and retirement was just too alluring!
my favorite designation, though, is my B.A.R. (no, not Browning Auto Rifle) -- my bullshit alarm ringer certification, granted by my wife who spent nearly 30 years in the medical business, facing patients, docs, nurses, techs, etc. generating bs!

you have to compute these ratios in absolute terms; 90 is 549.67 Rankine, and 60 is 519.67 Rankine, so that the ratio is 0.9454, or 1/1.058
this is not quite 1/3. the % change is 5.48%.
-- my professional engineer registration number is 12675 -- j