Memorial ratings down 31%

Thomas Bonk of the LA Times reports that CBS struggled in the ratings department on Sunday at The Memorial.  The network drew a 1.8 rating, down 31% from last year's 2.6. 

This is puzzling to me.  Rod Pampling was the third round leader last year, and Matthew Goggin led after three days this year (both led by three strokes heading into day 4).  Was last year that much more appealing?