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?
Many US jobs are based off an hourly rate, some with overtime (usually not added in). I noticed other posters mentioned Xmas bonus. As an hourly worker I received a standard 3% yearly raise to cover increased costs of living. Because our cost of living increase was nearly double that, our salary actually declined. Oh and that Xmas bonus... If you count a 25$ gift card to Walmart a bonus...
Federal Government can be nice because I'm salaried, but also get time and a half for OT, so I get the best of both worlds. On the other hand, we don't get performance bonuses, and our yearly COLA takes a literal act of Congress to decide on the percentage.
What agency? But from talking to the other people I work with, it's unusual if your boss doesn't put you in for some cash award a few times a year for me