During what period of time did they have some credibility and were they most active and making the most money?
Around here, when I joined back in 1987, there were so many pioneers in the congregation and they were in the field service morning, afternoon and evening.
That lasted about 5 years, then it was a quick and steady decline in field service and a decline in building new halls.
I wasn't a witness before 1987, so I don' t know if there were ups and downs in their preaching.
But they really are in a "down" period around here anyways.