I'm still occupying #1 spot on Google for one of my main KWs and I used to get hundreds of clicks for it but over the past few days the number of clicks has decreased dramatically. I've checked my webmaster tools and there are neither messages nor any other problems/errors. I've also checked my rankings both manually and using Google Monitor. According to this, I'm still #1. What could it be that has affected my website? How do I fix this? Thanks!