Traffic received at #1, #2, or #4

[selomelo]

On several occasions, I had the opportunity to observe variation in the traffic received depending on the SERP position. And my experience suggests that it makes a great difference when you are, for example, at #2 as contrasted to being at #4 and that being in the first page may not be sufficient.

Usually, my site ranks at #2 for a certain kw combination. But sometimes, as is the case now, its rank drops to #4 or #5. Whenever it is below #3, the traffic almost halves as compared to its normal level.

It seems that this holds true especially if the results page is highly relevant. The more the top 10 results are relevant, the lessser would be the traffic received by those sites below position #3.

Are there any similar or different observations?