I did that survey already. Results are:
< 20 --- 0 (0%)
20-30 --- 6 (2%)
30-40 --- 10 (4%)
40-50 --- 32 (13%)
50-60 --- 83 (32%)
60-70 --- 93 (36%)
70-80 --- 29 (11%)
Over 80 --- 3 (1%)
Works out to an average of about 55 years old.
Survey results
Bob