How much do illustators make pr year?

How much do illustators make pr year?
Too vaque a question. Full time, self employed, Work by the job/employer, full time. Type of illustrator really determines the fee or salary. I know a jobber type of illustrator. Been around for a while. He shops job or gets repeat business. He is an industrial illustrator. Makes into the 6 figures, but started out with his first account and only job that year, his first- around $22,000. Worked off and on for this client all year. But, 2 yrs. later, he made contacts and his ffirst company was bought by another, and took him a year to get the account back by showing his work was better and more professional and cost effective than their 3 illustrators. Now he works full time for this last employer and another. Works about 30-60 hours a week, depending on project, but is not an employee of either emloyer.