Have you looked at your Products Performance in last 6 months?
Since February 2013 Google started changing Google shopping in the UK. I was expecting dip on product clicks and this was matched with the screen shot above. It will be interesting to find out what yours look like. Simply log in your Google Base and click on performance to view similar screen like this.
Bear in mind this change will be completed by June 2013 and expect not to see any FREE clicks. The way forward would be to add on your products feeds to Google Adwords and test traffic and conversion results. Google calls it Product Listing Ads (PLA). I will write step-by-step procedure on next post. Until then here’s a short video for you to understand what Google Product Listing Ads (PLA) is.