Chronic Fatigue Syndrome Support Group
Chronic Fatigue Syndrome (ME/CFS) describes a sense of exhaustion and post-exertion malaise, even when you have gotten enough rest and sleep. The disease is characterized by six months of incapacitating fatigue experienced as profound exhaustion and extremely poor stamina, and problems with concentration and short-term memory. The cause is unknown, but it is a...
I have to head out for a bit but found this to start. I don't think you will get any exact numbers because no one knows. You can cite sources, etc.
My daughter is a librarian at a prep school. She has access to all sorts of information more easily than you or I. She is just back from vacation but I will see if she has time to do up a list of citations for you (and me).
http://en.wikipedia.org/wiki/Chronic_fatigue_syndrome
quoted from above: A 2003 review states that studies have reported between 7 and 3,000 cases of CFS for every 100,000 adults.[5] Ranjith reviewed the epidemiological literature on CFS and suggested that the wide variance of the prevalence estimates may be due to the different definitions of CFS in use, the settings in which patients were selected, and the methodology used to exclude study participants with possible alternative diagnoses.[10] The Centers for Disease Control reports that more than 1 million Americans have CFS and approximately 80% of the cases are undiagnosed.[11] Approximately 250,000 people in the UK are affected with the illness according to the National Health Service.[12]