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’m sure outside the US it’s even more customary, annual salaries are to include all bonuses.
That was my thought too. In Tech we do the same because of total compensation. Stock (options), bonuses etc. have a yearly cadence.
Also some places have a 13th salary, so yearly makes sense there too.
Generally we don’t include bonuses in annual salaries in the US because a bonus is not always guaranteed and many fields won’t have a bonus.