Hi Roger,
I'll be home for a bit if you want to call
Otherwise let's talk tomorrow
 
This is a plot of the NY var event (cum of 5 events) for different selections of timezones
I use the N largest zones, by pop, where N is the number of the zones.
so zone set 24 uses the 24 most populous timezones.
 
C30 and C20 are the complements of the 30 and 20 zone sets; these are sets with least populations.
 
I also looked at examination periods broader than the 10 minutes centered on midnight.
 
Most of the sets exclude 2 zones: Nepal and Chatham Islands. These zones are shifted by 15 minutes which makes the periods overlap when I look beyond -5 +5 minutes. Shouldn't be a big deal to exclude them.
 
It's interesting to see that the complement zones are indeed weak. More needs to be done for this analysis...
 
-Peter