Annual salaries will vary depending on where in the country you are and what type of company you work at.
Entry level job titles can range from "graphic designer" to "production artist" or some combination of those four words. Many companies outside of marketing, tech, and advertising need graphic designers, ranging from a copy/print shop, to a company that publishes a weekly paper, to a company that screen print shirts or engraves trophies, to a real estate or insurance company. These jobs may only pay $10/hr (that ends up being about $20,800 a year if it is a full-time job.)
But don't let that discourage you! I just don't want you to think that everyone graduates from their program and instantly makes $40k+ a year. Where the job is located will make a huge difference on entry level pay as well.
Getting a higher paying job right out of school will be dependent on your portfolio, not just how aesthetically pleasing it is to look at, but the types of projects as well. Strive for a wide range of projects to work on while in school: web design, various types of print, app ui, logos & full identity, and packaging. If you like drawing or lettering, having personal projects that show off your skills are very good entries to have as well.
Try your best to land at least one internship while you are in school because it will give you real work experience and portfolio pieces that aren't school projects to show. If you can't manage to get an internship, there are many non-profits that need help with small projects on a volunteer basis that you could do as real client projects to show in your portfolio. Also while you are in school, there may be some part time student jobs at the university or a college newspaper you can work at that give you valuable work experience and more things to fill your portfolio.
As far as the upper range, the sky is the limit depending on where you are working later in your career. More money will come from working in an agency setting or a large corporation where you climb the career ladder to be an art director, creative director, or head of something like creative services, product design, brand management, etc. Some employers won't really have much room to move upward, so your pay would go up just from continuing to work there with slow incremental raises, but it won't be as high.
And you will always be able to make a little more on the side with a freelance side hustle. Going full-freelance is always an option too! You set your own rates and set aside what you need for taxes, but are responsible for maintaining a workflow that works for the amount of money you want to be making.
I hope that gives you a more rounded picture of the very wide range of salaries out there for graphic designers.