Digital BW, The Print

I've been looking for some info on this without success, but I'll bet
someone on the list knows.  My Sony E500 21" CRT monitor is down to about
one week or less when it needs recalibration with the SpyderPro software and
puck (I can see it shift toward green in under a week).  The monitor is
about 4-5 years old now.  I was wondering what intervals are common for
re-calibration and whether this might be a sign of impending
replacement...and if so what would be a good replacement.  If replacement is
in the cards I like the size and sharpness of LCD screens, but I'm not sure
of my ground for Photoshop use (viewing a little off-angle, etc.). Any info
appreciated!!

Regards,

  --Ken Carney
    www.kencarney.com