Is anyone keeping a database of Cooke Portrait Anastigmat (i.e. with soft focus adjustment) lens serial numbers? I just picked up a 12.75" IIB and thought it would be interesting to start compiling serial numbers for Series I, II, & VI. Just in the last week I've been able to gather over 100 lenses worth of data and start to see some year/serial number connection.

Does anyone know when the transition from non-knuckler to knuckler started in terms of serial numbers? (1924 in terms of date, I know) I'm guessing somewhere around 115,XXX.
I'm also trying to establish the earliest serial number for each series since there is a fairly good sense of what year each series started.

I have a copy of the Lens Collectors Vade Mecum and I've checked various soft focus lens resources online (i.e. antiquecameras.net.) I'm putting together a Google sheet so that folks can add their lens series and serial numbers to the database if they like.