Thanks everyone! Keep 'em comin'!
So far, the data is yielding some impressive insights (no data yet in 2010 since no one has answered that they were baptized in 2010 or later):
Decade Average time to get out Standard deviation
1960 25.8 years 7.69 years
1970 22.1 years 11.89 years
1980 21.0 years 6.09 years
1990 14.3 years 6.90 years
2000 8.5 years 3.22 years
It is clear that 1975 led to a much higher variability, meaning that for a lot of people, 1975 truncated their stay with the Watchtower, but for a lot, it made no difference.
It is also clear (and very encouraging) that every decade without exception sees a lower average stay in the Watchtower, and also the lower standard deviation means that the factor that is reducing the time that people stay in the Watchtower cult affects everyone. And I am going to say that the factor is... obviously, the internet.
Now, my data may be skewed because I still have little data, I only have 70 responses, and the responses are naturally of people who are on the internet. Perhaps the people who came in the 70's are not on the internet and therefore will not participate on this survey.
In any case,
Thanks!