35s — CNA721: 2007 or 2017?

[cdmackay]

hi all,

Just picked up a 35s on TAS.

The serial number is CNA 72100328. How can I tell whether that's 2007 (which I assume means it's quite an early one), or 2017?

It came with the zippered hard case with the HP logo, which might indicate earlier, but of course that may not have been original with the calculator.

Here's a pic of the back, in case any of the other detail, or logos, dates it.

It does seem in very nice condition, which makes me think later. But an old thread on 35s serial numbers suggest most early buyers got 721…

thanks.