Les Binet did some sterling work thinking about share of search volume as part of his ongoing work looking at marketing effectiveness.
In order to understand share of search volume, we have to go back to 1990 when former advertising veteran and professor John Philip Jones[i] published a paper in the Harvard Business Review[ii] and a subsequent book[iii].
Jones’ research around the linkage between advertising and sales by looking at advertising including tools of his invention STAS (short term advertising strength)[iv] and AIC (advertising intensiveness curve). One of Jones’ key findings was the linkage between a brand’s share of voice and its market share. One of the biggest predictors of brand growth was ESoV (excess share of voice). ESoV is when a brand has a share of voice in excess of the proportion needed to maintain its market share.
During economic good times this might be down to an increase in brand building marketing spend, not only advertising and public relations, but also influencer and sports sponsorships with variable[v] results.
During recessionary times[vi], it might be maintaining brand building marketing spend when the competitors are cutting back.
Part of this brand building work overlaps with increasing marketing penetration through increasing the number of places where the brand is available. During the 95 percent of time that you are not in a buying mindset when you pass a product display in a supermarket it’s a billboard – doing the brand building work.
Jones’ findings were later validated by Peter Field and Les Binet’s work on marketing efficiency[vii], and in the summation of research[viii] from the Ehrenberg-Bass Institute for Marketing Science by Byron Sharp.
Share of search volume
The clever thing that Les Binet[ix] did with share of search volume[x] was find it as a predictor on the likely time when ESoV was likely to impact with a growth in market share AND, he found that the share of search volume change mapped neatly on to market share change.
The challenge is that different sectors have different times between a change in share of search volume and the corresponding change in market share[xi].
“For mobile phone handsets, Binet further ventured, share of search leads market share “by about six months” as a performance indicator – offering marketers a chance to adapt their strategies if needed if a decline is expected.
“If the brand … had access to the share of search data at the time, it would have had a six-month warning that share of market was about to turn around,” Binet said. “That’s an incredibly useful metric.”
Share of search’s predictive quality for energy brands, Binet explained, was noticeably shorter, at just “nought to three months.”
For automakers, by contrast, share of search anticipates market share by “nine to 12 months,” he said – a significant timeframe for marketers to potentially refine strategies.
Breaking out data for Volkswagen, the auto marque, provided corroboration that sales forecasts based on share of search “are incredibly close to what actually happened,” Binet said.”
Search considerations
Much earlier in my career I worked on the Yahoo! Search business, back when the company had its own search technology and sold its own search advertising. One of the things that we found was that while overall search volume could be modelled accurately for the year based just on January’s search data – unexplained search volume peaks still needed to be ironed out by looking at rolling three-month values instead.
I found it interesting that Binet’s findings didn’t seem the same degree of ‘peakiness’ and was a much more valuable predictor once the time lag factor between share of search volume and market effects were known.
Share of search makes sense from a logical perspective. Many below-the-line activities have been focused on search in terms of aiding SEO to increase share of market opportunity, rather than an explicit appreciation of the impact on the share of search volume and consequently change in market share. My friend James Warren used to talk about public relations and related earned media activities such as organic social media as ‘offline SEO’. This thinking was incorporated into Interpublic’s ‘inline’ concept[xii].
Future search
Share of search volume is complicated by a number of factors that are down to changing consumer behaviour.
Google’s focus on mobile upended the precision that we could search with and what we could search for, out went Boolean operators that could track down a highly relevant web page from 12 years ago. But we could now find the nearest coffee shop with wi-fi. YouTube[xiii] due to its explanatory content became the second largest search engine globally (excluding China).
A good deal of product search has migrated to sites like eBay, Walmart[xiv] and Amazon[xv]. Part of the reason being is that their site search is good enough, they have a wide range of stock and speedy delivery. Amazon also benefits from Amazon Prime which drives customer purchase, but isn’t without controversy[xvi].
Social and generative AI have unlocked new challengers to Google. Search on social platforms has become the go-to approach for many young people. Google acknowledged this when asked by Business Insider[xvii].
“we face robust competition from an array of sources, including general and specialized search engines, as well as dedicated apps.”
The move to social is about tapping what we called back in my Yahoo! days ‘knowledge search’[xviii]. Search startups like Gigabrain have tried to tap into this market by providing a better search function of Reddit forums.
Finally, the move towards consumer usage of generative AI tools based on large language models has created new competitors to Google including Perplexity and ChatGPT Search. Google itself has adopted LLMs in its own search offering and seen an increase in both revenue and profit from search advertising[xix].
Share of model vs. share of search volume
In order to try and understand new LLM-driven search, innovator agencies like Jellyfish and Deft[xx] have looked towards understanding share of model. Share of model tries to understand how LLMs perceive a given brand, in a similar way to the way SEO rankings held a similar place in search engine marketing. Like SEO, they look to understand whether the brand has sufficient optimisation of their digital properties to feature in recommendations by the models.
What share of model doesn’t give us is the consumer insight provided by share of search volume. Share of search volume is consumer behaviour driven and advertising influenced; share of model is algorithmic behaviour driven and training influenced.
[i] John Philip Jones profile (United Kingdom) WARC
[ii] Jones, J.P., (1990) Ad Spending: Maintaining Market Share (United States) Harvard Business Review
[iii] Jones, J.P. (1995) When Ads Work: New Proof That Advertising Triggers Sales (United States) Jossey Brass
[iv] Hansen, F., Olsen, J.K. STAS and Other Short Term Advertising Effect Measures (United Kingdom) WARC
[v] Siu, A. (February 2025) The Honey scandal is a ‘wake-up call’ for the creator industry’s affiliate partnerships
[vi] (2023) The power of excess share of voice (United Kingdom) Thinkbox
[vii] Binet, L., Field, P. (2013) The Long and the Short of it: Balancing Short and Long-Term Marketing Strategies (United Kingdom) Institute of Practitioners in Advertising
[viii] Sharp, B. (2010) How Brands Grow: What Marketers Don’t Know (United Kingdom) Oxford University Press
[ix] (2020) Share of search can predict market share (United Kingdom) WARC
[x] Binet, L. (2021) Share of Search (United Kingdom) Les Binet channel on YouTube
[xi] (2020) Share of search can predict market share (United Kingdom) WARC
[xii] Warren, J. (2008) Back to school (United Kingdom) PR Week (republished on PR 2.0)
[xiii] (2010) YouTube Revenue Approaching $1 Billion Per Year [REPORT] (United States) Mashable
[xiv] Levin, M.R., Lowitz, J.N. (November 2020) Grocery Drives Walmart Online Orders (United States) Consumer Intelligence Research Partners LLC (CIRP)
[xv] Evans, B. (2023) Retail, search and Amazon’s $40bn ‘advertising’ business (United Kingdom) Benedict Evans
[xvi] Stoller, M. (2021) Amazon Prime Is an Economy-Distorting Lie (United States) BIG by Matt Stoller
[xvii] Delouya, S. (2022) Nearly Half of Gen Z Prefers TikTok and Instagram Over Google Search (United States) Business Insider
[xviii] Carroll, G.M.S. (2021) Yahoo Answers (United Kingdom) renaissance chambara
[xix] Morris, S. (2025) Alphabet shares gain as Google search boots profits (United Kingdom) Financial Times
[xx] Crocombe, I. (2025) Share of Model (United Kingdom) Deft