Evidence
Sources and references
Every source we cite on this site, in full, with a link to the full text where it is freely available, or to the publisher’s page where it is not.
How to read this page
References follow the APA (7th edition) style and are listed alphabetically. When a source is cited elsewhere on the site, its name links here, and the entry it points to is highlighted.
Most of the figures we use come from surveys of business decision-makers. They show what people say they think and intend to do, not what they were seen to do. Where a source is produced by an organisation that sells related products or services, we say so beneath the entry.
Anderson, C., & Marshall, A. (2025). The ROI of thought leadership: Calculating the value that sets organizations apart. Wiley. Publisher’s pageBook. Not free to read online. Both authors work for the IBM Institute for Business Value, so the 156% figure is the authors’ own research.
Dawes, J. (2021). Advertising effectiveness and the 95-5 rule: Most B2B buyers are not in the market right now [B2B report]. Ehrenberg-Bass Institute for Marketing Science and LinkedIn B2B Institute. https://marketingscience.info/news-and-insights/advertising-effectiveness-and-the-95-5-rule-most-b2b-buyers-are-not-in-the-market-right-nowFree to read online. The 95-5 rule is a rule of thumb, not a measured constant; the author notes the percentages should not be read literally.
Ebsta & Pavilion. (2025). 2025 GTM benchmarks. Ebsta. https://benchmarks.ebsta.com/2025-gtm-benchmarksRegistration required. Produced by a sales-software company from its own customer data.
Edelman & LinkedIn. (2024). 2024 B2B thought leadership impact report: Reaching beyond the ready. Edelman. Full report (PDF) · Report pageFree to read online. A survey of 3,484 business leaders in seven countries (fieldwork 30 November to 14 December 2023). It reports what people say, not what they did.
National Audit Office. (2021). Evaluating government spending (HC 860, Session 2021–22). House of Commons. https://www.nao.org.uk/wp-content/uploads/2021/12/Evaluating-government-spending.pdfFree to read online. Covers central government’s major projects; the figures are for 2019.
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