The Degree is not a Passport to earnings. It is merely an indication that you are capable of learning something.

When you get your first job, you will be just as dumb as everyone else until you learn the job.

As to how much you can earn, that is up to you, not your degree!

Computer Science (CS) has various fields or areas such as communications, software programming and languages, and modeling which relies heavily on mathematics which itself has various areas…plus you might wish to link CS with another discipline such as Electrical Engineering, Physics, etc. If you work or do research for a company, check to see what royalties you receive on top of your salary. Generally speaking, you should earn more than the average wage, but remember that things get obsolete quickly in CS–so you can’t rely simply on that B.Sc.–you will be sent to courses to learn new things besides that which you learned to get your B.Sc.