The large drop in Z1 is explained by not counting the entries with expired domains and no other listed contact method. They are "dead" whether the concerned *C removes them or not.
These probably are not the final figures. There are so many listed sysops now with virtual systems in the cloud, somewhere, anywhere not tending to that system anymore that it is safe to assume the real numbers are way lower ... plus there is dead-wood ... segments which have not been maintained for ages. When a segment lists batches of entries with just phone-numbers, then I get suspicious.
The counting method:
* Remove administrative overhead and comment lines
* Remove all temporary 999-style lines
* Remove all double sysop names
* Remove all silly sysop names not refering to a sysop but to a function
* Resolve silly doubles such as "TJ Barlow" and "Terry Barlow"
* Remove special wise-guy cases
* Remove expired DNS references
* Origin: International Coordinator (2:2/1000)
Mon Nov 20 12:11:16 2023
Fri Nov 24 22:16:15 2023
Sun Nov 26 08:45:51 2023
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