Cannondale year from serial number?

I'm attempting to determine the year of manufacture of a Cannondale CAAD3 road frame. There is a
previous discussion here identifying the Cannondale serial number code for older bikes (on the
chainstay), but that format doesn't agree with the serial number code from my bike, located under
the BB. Anyone have an idea of how to interpret the info from newer Cannondale serial numbers? FWIW,
the serial numbers of my bike have the following format: ID B1-0302 19607 237146 7BON50

Since my frame is a 50cm, I'm guessing that the last two characters are the frame size. I'm guessing
that my bike is 1997-1998-1999. Since there are no 8s or 9s in the code, but two 7s, perhaps that
makes my bike a 1997? Any help from a Cannondale expert?

Thanks...Todd