Something which stands out to me, using the average percentage increase in publishers is the different phases.
The post-75 exodus with falling numbers. Reversed with the Reagan era nuclear holocaust fears and build-up to 86 and maintained as communism collapsed. Then the collapse at turn of the millenium which is partially masked by the 2002 changes to reporting 15 minutes if elderly/sick and then the financial crisis.
Is this the centennial step down then? The 100 years after 1914? Does it usher in a drop to marginal (ie 1% and less) percentage gains, or a decline? If not a decline, then the next step down will certainly be full flatline and decline. 1914 and its generation is the millstone for them. Pinning prophesy to events gives them the boost in numbers, but the comedown for being wrong hammers them worse each time.
Demographics are hammering them. They have to have 3 kids to keep 1 in - 6 just to maintain numbers across a (non-overlapping) generation. The average age is rocketing up. Even now they're preaching to women unable to find a partner the virtues of staying single past the age of being able to have children rather than encouraging marrying outside of the organisation. Whole congregations can go a year preaching with the only baptism being a born-in. Such a waste of so many lives. Kind of sad watching people still clinging to it as it slowly implodes. And that includes my family.