I think this is mostly a US thing. Why use yearly salary? You’re not paid once a year, are you? Most likely once a month. Referencing monthly salary makes much more sense.
“I’m making 50k”. Great, now I have to guess - dollars? Monthly? Yearly? If yearly then what’s the monthly paycheck? Net? Gross?
I work OT as well, and it’s feast or famine. I’ve had 30% of my yearly salary come from a little over two months where I worked 12/7s. Hourly rate doesn’t really get that across.