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?
Not in basically all of the English speaking world. USD, CAD, AUS, Pounds, Euros, NZD. 50k a month or week or whatever you for some reason think it might be other than a year would be an insane amount of money to make.
I bet you're the kind of person that hates it when you ask the time and people respond by rounding it to the nearest 10 minutes...