Sometimes good ideas outlive their usefulness as the underlying terrain changes. In my opinion, such is the case for most Spot TV Post Buy Analyses.
For a long time, post buys known as "posts" were a good thing in the local marketplace. It kept spot market negotiators on their toes, kept agencies honest, and it was a useful tool to determine the skill of a buyer. For clients it served as something of a report card for their agencies. Broadcast stations also used it to monitor their performance and to get the measure of with whom they were dealing. Station personnel were often surprised to find that agencies of even modest size had the best forecasters on staff and could see who was truly stewarding buys compared to those who played "set it and forget it' and moved on to the next market's negotiation.
In recent years, the value of posting has lost some of its luster among thoughtful media people at agencies, stations, and advertisers alike. It is particularly acute in markets that still use diary measurement. The diary method of measurement launched in July 1950. A lot has changed since then and Nielsen has made an effort to improve the methodology. But, it is absolutely incapable of capturing activity across a few hundred separate channels in 2009.
And, think of the response error that you get with a diary base! What self-respecting 21 year olds are going to dutifully fill out a log of their viewing for a week and mail it back to Nielsen? Probably a bunch of young nerds who fantasize about becoming IRS agents or life insurance actuaries. Do they represent the habits of their generation? Of course not, but Nielsen reports them as doing so.
Also, the diary does a terrible disservice to local cable sales as only a handful of channels show up in a diary based rating book. It has been very instructive over the last several years to watch what happens when a market switches from household Nielsen meters to Local People Meters (LPM). The affiliates take a hit, local news tanks big time, and cable numbers absolutely zing upwards. So, diary numbers are two steps removed from LPM methodology. But LPM, as it rolls out across the country is itself being questioned as fighting the last war as streaming video and DVR penetration change the advertising game dramatically.
So, smaller advertisers, operating in markets ranked approximately 65-210, only receive diary data. Admittedly, not as much money is spent here as the top 25 DMA's (Designated Market Areas), but broadcast negotiators are often asked to post as well in these smaller DMA's as they are in the giant markets with daily meter data on both a household and demographic basis.
The situation is not all Nielsen's fault. It is expensive to go to household meters and more so to LPM. One market, #39 ranked Grand Rapids, still uses a diary as local players will not pay for a meter. (Many markets ranked in the 60's have household meters) But, as they roll LPM out to more DMA's, it is a tacit admission that the diary is obsolete and has been for some time. (Arbitron faces a similar issue in Radio)
Across the country many fine broadcast negotiators get beat up in client meetings because they did not post above 90% in a diary market. Yet, with every passing rating book crazy things are happening. Zero cells abound even in primetime. I dare you to look at a 3rd quarter rating book in a diary market. It is stunning. Sometimes, a strip program (telecast same time Monday-Friday) will have a 3 on Monday and Tuesday, a zero on Wednesday, and 2's on Thursday and Friday. To post in early fringe these days often mean getting a lucky rotation. It is madness.
Over the years, I often quietly conducted analyses that looked at post buy performance and pitted it against retail sales. Sometimes they matched but often sales jumped when posts were under the 90% performance standard and other times they tanked when the post was 120%+. Of course, there are many exogenous factors in play--strength of the creative, appeal of the offer, execution at retail, state of the economy, and always, what was the competition doing.
I can only say this--sales results are a far better indicator of media performance than any post buy analysis can ever hope to be!
Finally, here is an issue that media people often ponder but never say out loud. Agencies, buying services, and clients want each station to post at 90-100% of forecast. But, what of stations that consistently deliver? Do they get paid more? Do they get a thank you? Shrewd negotiators often increase the shares of those stations that monitor the buys closely but given the vagaries of the Nielsen diary base, perfect posting is often impossible in the world of 2009 TV.
I am not naive. Nielsen is the currency that we have to use for the next few years. But, if you are an advertiser reading this, have some common sense. As TV viewership crumbles over the air and scatters everywhere else, lessen the importance of post buys in your agency evaluation especially in diary based TV markets. If you must use it, look at it over a year or 18 months rather than a 4 week flight. The measurement is deeply flawed and the world is changing rapidly.
If you would like to contact Don Cole directly, e-mail him at firstname.lastname@example.org