When we talk about “impressions,” we’re talking about the estimated number of people tuned in at a given time. TV and radio stations provide several different metrics for impressions: Cume impressions, household counts, and average impressions. As you’re about to discover, these three figures are not interchangeable: they each paint vastly different pictures of the same ad spots, and knowing which one to follow is crucial to making effective use of your advertising investment!
Cume (short for “cumulative”) impressions is the number of people tuned into a station for at least five minutes during a specific period of time, usually represented in thousands. However, those five minutes could be any five minutes during that time period, not necessarily the ones your commercial airs during. In practice, Cume impressions are the total number of viewers for a given time period, which usually comes out to about ten times the number of people who will actually see your commercial – for example, if a station tells you they have Cume impressions of 100,000, that usually means an average audience of only 9,000-10,000. Hardly the princely number it appears at first!
Household counts are precisely what they sound like: how many households there are in the specific market area that the station covers, whether over the air or via the cable grid. Like Cume impressions, however, household counts give an inflated estimate of how many people your ad will actually reach. Even if your ad can reach radios or TVs in those households, how many people will actually be tuned in when it airs? The answer: not as many as you would think. Household counts give you no guarantee that the people in those households will actually be watching or listening – or even at home in the first place!
Last but not least, we come to average impressions. These are the useful ones – the figures that will tell you whether an ad spot is a good deal or a waste of your advertising money. Average impressions, as the name implies, refers to the average number of people who are watching or listening to a given channel at a given time in a given market area. These are usually represented in thousands, like Cume impressions, but also as a percentage of the total potential audience of a given demographic – a number you might be familiar with in the form of Nielsen ratings.
As an advertiser, you need to carefully pick and choose where to invest your budget to ensure your advertising reaches the people you want it to. Before you buy airtime, make sure you know the average impressions: that way, you can laser-focus your investment so that every dollar you spend stands the best chance possible of translating directly into advertising success.