In advertising, the Click Through Ratio (CTR) is an indicator for measuring the effectiveness of an online advertising campaign. The proportion of clicks is obtained by dividing the number of users who clicked on a publicity piece -banner- by the number of impressions shown of the same, expressed as a percentage.
The average CTR accepted in display advertising campaigns was 0.12% at the end of 2011, but currently 0.10% is a figure accepted due to the saturation of advertising users suffer.
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