In Google AdWords reporting there is an option for evaluating your campaigns Impression Share (IS). This report is a good guide for assessing your market share for the keywords live in your account.

Most marketers would hope to see 100% IS for brand terms; however there are some reasons why it is unlikely you will observe an overall IS of a 100%.

• You have 0% Impression Share (IS) lost due to budget. Daily caps should never restrict your Brand campaign.

• Lost IS due to rank is caused by phrase, broad and most importantly extended broad matching on irrelevant or competitive keywords. There is no missed opportunity on this keyword as it does not generate the right performance metrics.

• By generating a Search Query Report you can analyse the search queries where your keywords are ‘extended’ broad matching on to, you will most likely be matching onto irrelevant queries possibly competitors. Your Quality Score will be low for these competitor/irrelevant keywords and therefore you will lose out on impressions for this search query. Add negatives for these keywords.

So next time you look at a report from Google bear in mind that impression share might not be a true picture of the PPC landscape.