Here are the results from Sweet et al, 2003 in the Archives of Clinical Neuropsychology. I have no real reason to believe that age was a major variable unless you did a good deal of Medicaid and that averaged 10-12% across all respondents. This survey is up again in 2008, so we should get new numbers. I'll post it when I get it. There is a wealth of other useful data in it as well.
"Respondents were asked to provide their gross professional income from all sources as a psychologist, rounded to the nearest thousand. Of the total sample, 1,406 individuals provided income information. Of these, there were 1,164 who could be classified as working full-time as licensed doctoral psychologists with at least some active involvement in clinical practice. This latter sample had a mean income of $104,132, with a median income of $83,000. The large difference between mean and median indicates the lack of normal distribution of incomes. Also, the large standard deviation of $76,288 and the extremely large range of $6,200$980,000 were concerning. Therefore, the 1st and 99th percentiles were identified ($20,000 and $400,000, respectively) and 20 individuals outside of these limits were excluded from further income analyses on the basis of being statistical outliers. The resulting gross average income was $100,480, with a median income of 83,000 and standard deviation of $57,767.
Stratifications of income in Table 11 depict the frequency distribution among the respondents. Approximately 70% of the respondents have incomes between $60,000 and $160,000. Approximately 75% reported incomes below $120,000, 95% of individuals reported incomes of $240,000 or less, and 98% reported income of $296,000 or less."
