I will let you know what happens when I press each one numerous times, I'm currently waiting for the resistors to come. and I'll fix that bug, but it still seems pretty unnecessary. 
if it is one of those values, who's to say which key it represents? If I use the serial monitor and get the value that comes up for each one, and split the difference between each key, it should never come close to the extremes.
I mean, what could go wrong if we only use 2 digits to represent the year??
-carl