12 May
2011
12 May
'11
5:15 p.m.
The actual number would be considerably smaller as there were large (for some definition of large) block assignments of ASNs <~1000 or so to various academic networking entities such as NSFNet and regional networks as well as other Federal/Military networking organisations.
-dorian
Well, for one data point, I was issued 3492 around Spring of 1994.