Most likely there are more searches done than your add is displayed for. The number of impressions depend on your daily budget, your average CPC and your CTR. How many real searches are done should be no concern.

Imagine your daily budget is $100 and you´re willing to pay 50 cents per click on average. That means you'll get about 200 clicks per day. Now Google will simply do a calculation. They look at the history of your CTR to predict how many impressions are needed to give you 200 clicks. Suppose your CTR is about 2 %. That means for every click 50 impressions are required. 200 clicks times 50 impressions means about 10,000 impressions. So they'll give you 10,000 impressions.

Of course it is possible that a certain keyword doesn't have that many impressions. In that case they won't be able to spend your complete daily budget. (and they won't) In this case it is your job to find more keywords so that you can reach more searches to get the required clicks you want.


The above is a bit simplistic view of how Google works. They have many more variables to play with to get you the best result. That means for example that when the adwords system realizes that its not able to spend your complete budget in one day, they´re going to move your ads up a position for a while so you'll get more clicks. The opposite is possible too. When clicks are going too fast, they will lower your positions a bit in order to reduce the speed at which your budget is spent. (lower positions get less clicks.) That's why they give you an average position rather than an exact position. Then all this is being done while keeping in mind the other advertisers so that they also get the best result for their money. The amount of variables is huge and makes the whole thing pretty complex. But they´re pretty good at dealing with that at Google.

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Otimização de Sites (SEO in Brazil)