An elevated D-dimer level is not normal. It is usually found after a clot has formed and is in the process of breaking down. If you are having significant formation and breakdown of blood clot in your body, your D-dimer may be elevated. A negative D-dimer test means that a blood clot is highly unlikely.
Purpose [edit]. Counting impressions is the method by which most Web advertising is accounted and paid for, and the cost is quoted in CPI (cost per impression) .
Impression share (IS) is the number of impressions you've received divided by the estimated number of impressions you were eligible to receive. Eligibility is based on your current ads' targeting settings, approval statuses, bids, and quality.