HOW LONG DOES ADVERTISING LAST?

Summary from the TLDR Marketing newsletter

The advertising industry is divided between advocates of long-term brand building and short-term performance. Studies indicate that if an ad campaign doesn't perform well initially, it likely won't improve over time. Financial returns from advertising can start as early as 61 weeks, but often take up to 150 weeks. Advertising has a significant carryover effect, decaying at about 30% per year. While traditional media is often seen as superior, newer research indicates that online, content-integrated ads are far more effective.