Whether you’re new to digital advertising or a seasoned veteran, it can be difficult to stay up to date on trends affecting your campaigns. One of these trends revolves around the most rudimentary of metrics, Cost Per Mille or CPM — The price advertisers pay per 1,000 impressions on a given website.
Our Media Analysts live and breathe campaign analytics, and CPM is watched carefully all day because it is the baseline metric that affects all others. Fluctuations in CPM have a direct impact on RPU, and the overall financial performance of your site. They are one of the key metrics to track as you manage and refine your goals.
From a high-level perspective, CPM can be thought of as a staircase. CPMs generally rise over the course of the year, quarter, month, and week. However, according to our data, CPMs tend to drop throughout the day.
That may sound counter intuitive, but let’s dig deeper.
Daily CPMs are at their highest mid-morning, then decrease throughout the day and generally “reset” at midnight. By “reset” we mean: new day, new budget (for advertisers). The rates jump from their end-of-day lows back up to something closer to their peak, at midnight. Then they go on to reach their peak mid-morning, and repeat.
CPMs generally rise over the course of the year, quarter, month, and week. However, according to our data, CPMs tend to drop throughout the day.
Daily CPMs fluctuate in the opposite fashion of weekly, monthly, and quarterly CPMs. The beginning of the week (Monday) sees the lowest rates of the week, while the average CPM increases slowly throughout the week, peaking over the weekend.
Likewise, monthly rates see an increase month over month throughout the quarter, with the lowest rates appearing in the beginning of the month. Quarterly rates follow the same pattern, with Q4 seeing higher rates than Q3, so on and so forth.
Be very conscious of times when any of the aforementioned observations happen simultaneously. For example, be exceptionally conservative with your bids when the 1st of the month falls early in the week, i.e., Monday or Tuesday.
Some outliers to this include holidays like Thanksgiving and Black Friday. CPMs will often spike over holidays, especially holiday weekends.
With this understanding of CPM trends, you can begin to refine your forecasting, and begin testing this theory against your own data. However, keep in mind that different publishers will see subtle shifts in these trends based on their content and reader behavior.