We now have 3 ESTIMATES BY BERNARD. He is honest to acknowledge them all in the last post on the matter. 89% (made on Facebook earlier), 85% and 83%.
The 83% was his first estimate from the Vol. 3 book.
No statistical data collection with corroborating evidence from a large or even a reasonable sample but rather one guesstimate and McClintock, Scism, and Kinzie saying the PCI was in the minority. Bernard then takes liberties to tell us what this means and what they meant. This falls short of anything resembling qualitative research.
Hall's 90% estimate is supported by an appeal to authority. He is labeled by the Bernard as the foremost UPCI and Oneness historian until his death. Hall was the curator of HQ archives for many years.