A number of factors affect the reach and frequency of a campaign. Before planning your campaign you should think about the brand you are advertising and ask yourself some initial questions. These might include:

• How established is my brand?
  A more established brand may be able to reduce frequency if it is already very well known.
• Who am I trying to reach?
  It is important to understand your target audience. Some audiences will need to see your message more times than others.
• Is my target audience easy to reach?
  Smaller, more niche audiences, such as light viewers or AB men, will be harder to reach.
• What is the aim of my ad?
  If you want to persuade your audience to change their opinions on something they may need to see your message more often.
• Will it be a complicated or simple message?
  Simple messages may only need to be seen once or twice, whereas more complex messages will probably need to be seen more.
• How saturated is the market?
  If the market is saturated then you may have to expose viewers to your ad more often in order for them to remember your brand.
• Will consumers be making a high or low consideration purchase?
  Consumers may need to see ads with a high considered purchase, such as a car, more often than a product which is more of an impulse buy, like food items. By the same token, impulse purchases often happen more frequently, which will have implications for the frequency within the average purchase cycle

All of these issues will affect what you will be aiming for in terms of reach and frequency. But is there an optimum level of each?

Krugman’s argument for effective frequency takes shape in the form of his “Three Hit Theory.” This is when the first time someone is exposed to your ad you attract their attention, but nothing is really taken in, thus “What is it?” The second time is when the viewer begins to engage with the relevance of the ad, “So what?” And the third exposure to the ad is when the viewer decides whether it is “for me” or whether they will choose to “forget it.” ¹  He argued that every time the ad was seen after the third time, the decision made from the third exposure was simply reinforced. NO new opinion is formed after the 3rd exposure. This idea only changed when a significant amount of time had passed first, in which case the viewer would start at stage one again.

Krugman’s theory was supported in Mcdonald’s study of switching behaviour and it also reinforced Naples’ findings in his 1979 study of Effective Frequency. Naples drew several conclusions from his research, one being that “optimal exposure frequency appears to be at least three exposures within a purchase style.” ²  The so-called “purchase cycle” would obviously differ by product categories. Naples also supports Mcdonald’s study, as he says: “The study by Colin McDonald offers by far the strongest evidence in favour of two-exposure effectiveness, since his results related directly to purchase cycle.” 

This theory may not be true in regards to firmly established brands. A well-known brand may choose to concentrate more on coverage instead of frequency, trying to get as many people in their target audience to see their ad, but they have the luxury of not having to stamp their brand name into consumers’ minds. Once a brand is easily recognisable and established, the job of the ads is more to remind consumers of their product(s) and continue to keep their share of voice in the market. This is more important if the market is saturated, as the more competition there is the easier it is for your brand to be forgotten. 

When considering effective frequency it is useful to observe the advertising response curve. In 1989 Michael Stankey noted that effective frequency implies an S-shaped response curve, resulting from effectiveness rising radically after ad exposures have accumulated.

Simon and Arndt’s research disagreed with this and they point out that only two other studies (McNiven, 1969 and Rao and Miller, 1975) support the S-shaped curve theory, perhaps making the theory less credible. Simon and Arndt made the conclusion that “the studies using physical and monetary variables add up to the conclusion that there are not increasing returns to advertising, that is, no S-shaped response function – over the normal operating range.” ³

Blair studied just under one hundred case histories of projects that were carried out by Research Systems Corporation, who were looking into advertising wear-in and wear-out. The study acknowledged the idea of effective frequency, but the conclusion Blair comes to seems to contradict his actual results. Blair states that “there is a ‘wearing-in’ process which occurs between the advertising and the consumer” and then goes on to say that several “household exposures, or ‘frequencies,’ are probably necessary to achieve effective delivery to the consumers in these households.” Even though what she says would seem to support the S-shaped response curve, the response curves of the case studies in the study showed diminishing returns and were concave. ⁴ There have many other studies that also support the concave shaped response curve including Zielske and Henry (1980), Schultz and Block (1986), Wenzel and Speetzen (1987), and Stewart (1989). ⁵

Another factor to be considered when discussing frequency is whether all people will need to be exposed to ads the same amount of times for the ads to have the desired effect? All viewers would have to respond to roughly the same threshold in order to justify the theory of effective frequency. ⁶

Steiner believes that the S-shaped curve may be a consequence of consumers liaising with retailers. Consumers first begin to react to advertising they have seen and then the advertisers react to that by supporting the product more, which then increases sales. This is not really an example of effective frequency however, but simply an illustration of concentrated advertising at the beginning of a campaign. ⁷

All of these theories can be used in different ways when planning TV campaigns, and it becomes clear that there is not  one finite answer to the question “what is the optimum frequency?” Each theory can be used on assorted briefs, all dependent on those brand and product related questions, outlined at the beginning of this article, that need to be considered before producing a plan.

“The Frequency Thermometer,” described by White and Dawson, is another method  of assessment for the appropriate level of frequency on a plan. “The Frequency Thermometer” reflects the evidence regarding new and established brands: “Lowest frequency for simple reminders, teasers, simple responses; highest frequency for introducing new concepts, new products or changing earlier associations.” ⁸ They look at TV frequency compared to all media, suggesting having separate “thermometers” for each medium. White and Dawson then suggesttaking an average frequency in the most cost effective way from comparing all the results.

Of course, the creative aspect of an ad is also extremely important when considering levels of effective frequency, and is also a reason why all of these theories could be totally irrelevant. If the creative is genuinely good or unusual,a person may see it once and play it over and over again in their mind, talk about it with other people and search for it online. On the other hand, an ad can be seen multiple times and can be ignored because it lacks the creative character to make a connection with the audience.

From our own research at Thinkbox we have discovered that emotional ads are more likely to be remembered (in the implicit mind at least) than more informative ads. This is due to the fact that whereas informative ads stimulate our explicit/conscious mind, emotional ads engage our implicit/emotional mind. As a consequence of this we are more likely to remember those ads that motivate our implicit minds, perhaps resulting in viewers needing less exposure to your ad or only needing shorter forms of the ad to evoke similar responses.

Since then recency planning has almost taken the place of the two or three-hit theory according to Advertising Reach and Frequency: What Really Works, however whether that is also right for every campaign is also questionable. New brands for example, would probably need a heavier weighted campaign to get the attention of the audience, particularly at the beginning of the campaign and if the brand was new to TV.

Although it is important to reach effective or optimum frequency in campaigns, for those light viewers and niche audiences, a well placed ad seen once can be more beneficial than 10 ads placed in programmes that will not be watched. For light viewers in particular, recency can be more important than frequency. For example, for a food brand which has an immediate point of sale, recency is about having your ad as the last message viewers see before they make a purchase/decision.

When comparing frequency and reach, Ephron describes the effective frequency theory, which argues that advertising works through repetition, like stuffing a turkey. A reach based planning strategy however is “more like waiting for hungry fish to bite.” ⁹ In the same article Ephron goes on to say that:

 'stuffing turkeys' is how TV used to work - when many products were so new consumers had to learn to need them - and 'fishing' is how it works today. You don't have to teach consumers about consumables anymore. They know them and buy when the box is empty - or, in the case of durables, when the product wears out or breaks. The primary role of advertising is to influence the brand consumers select. To get them to buy your brand, you need to reach them when they are ready to buy a brand.

Ephron takes this idea and argues that “the real target isn't consumers, it's their purchases.” Because consumers make purchases every day of the year, planners should not use bursts for advertising, but should be continually reaching them throughout the year. He terms this idea “renting-the-shelf” advertising and believes that planners need to “forget about frequency and learn to plan and buy for weekly, and in some cases daily, reach.”

If we take a look at reach figures over the last 5 years we can see that there is little change.

From looking at this table it is evident that, for these three audiences at least, buying 100 TVRs in 2003 compared to buying 100 TVRs in 2007 gives you very little change in the reach %. The numbers tend to be going down slightly every year, however individuals have increased recently. This is most probably a consequence of the growth of multichannel. Individual impacts were up 3.9% year on year in 2007 and are currently up 5.9% year on year in 2008. ¹⁰

Since the growth of digital channels began, it is often assumed that it is now more difficult to achieve optimum coverage and frequency. As there is now a much wider choice of channels and the majority of homes now have Freeview, Sky or a multi-channel equivalent, how is it possible to reach as many people through TV? It is actually not that different. A mock up campaign based in June 2008, buying 400 ABC1 Adult TVRs shows that if you were to buy just terrestrial channels you would get a 1+ cover figure of 75%

By adding multichannel to this campaign, coverage can be increased to 79%

It is impossible to come up with one magical number for effective reach and frequency. There are many theories, all of which can be verifiable or falsified, and all of which offer another opinion or view on one of the most frequently asked questions when it comes to TV planning. The important thing is to flight the campaign in the way that best suits the objectives for the brand.

References

¹H Krugman, "Why three exposures might be enough," Journal of Advertising Research, December 1972
²M Naples, Effective Frequency: The relationship between frequency and advertising effectiveness, Association of National Advertisers, New York, 1968
³M Stankey; "Isolating the Efficient Operating Range for Advertising Media" in Proceedings of the 1989 Conference of the American Academy of Advertising, California American Academy of Advertising 1989
⁴M Blair, "An Empirical Investigation of Advertising Wearin and Wearout," Journal of Advertising Research 27,6 (1987)
⁵H Cannon & W Riordan; "Effective reach and frequency: does it really make sense?" Journal of Advertising Research, Volume 34, no.2 March/April 1994
⁶H Cannon & W Riordan; "Effective reach and frequency: does it really make sense?" Journal of Advertising Research, Volume 34, no.2 March/April 1994
⁷L Steiner; "Point of View: The Paradox of Increasing Returns to Advertising," Journal of Advertising Research 27, (1987)
⁸C Dawson & S White; "Frequency and recency: keeping your customers close," Admap, July/Aug 2003
⁹Ephron,, E; "More Weeks, Less Weight: The Shelf-Space Model of Advertising," Journal of Advertising Research, Vol. 35, No. 3, May/June 1995
¹⁰Source: BARB, DDS based on Jan-Sep, equivalent individual impacts