In 2009 persuasion likely accounted for 30% of the U.S. Gross Domestic Product (GDP), or about 4.56 trillion dollars. What percent of GDP was due to persuasive public speaking?

On January 4, 2019 at Inc. there was an article by Carmine Gallo titled Public speaking is no longer a ‘soft skill.’ It’s your key to success in any field. A section on The Growing Value of Changing Minds began:

“In a world built on ideas, the persuaders – the ones who can win hearts and change mind – have a competitive edge. I’ve spoken to economists and historians like Deidre McCloskey at the University of Illinois, Chicago. She conducted an impressive research project to prove that old fashioned rhetoric – persuasion – is responsible for a growing share of America’s national income.

McCloskey analyzed 250 occupations covering 140 million people in the U.S. She created a statistical model based on the amount of time people in each category spent on public speaking and persuading another person to take action. In some cases persuasion played a more limited role than others (think firefighters versus public relations specialists).

McCloskey reached the following conclusion: Persuasion is responsible for generating one-quarter of America’s total national income. She expects it to rise to 40 percent over the next twenty years. McCloskey’s research was taken up by another economist in Australia who reached a similar conclusion.”

The Australian economist was Gerry Antioch, who discussed his research on the percentage of the Gross Domestic Product (GDP) in an article from 2013 in issue 1 of Economic Roundup titled Persuasion is now 30 per cent of US GDP (revisiting McCloskey and Klamer after a quarter of a century). That earlier article by McCloskey and Klamer was published in the May 1995 issue of The American Economic review on pages 191 to 195 and titled One Quarter of GDP is Persuasion. Table 1 of Antioch’s article shows the details of McCloskey and Klamer’s “inspired guesstimate,” of 26% for 1993 - which actually includes just 21 of those 250 occupations. There were four categories with weights of 1.00 (4 occupations), 0.75 (9 occupations), 0.50 (6 occupations), and 0.25 (2 occupations). They also made estimates from data for the years 1983, 1988, and 1991. Antioch made estimates for 2003 and 2009.

The first bar chart shown above presents the percentages for persuasion from all six estimates. A second bar chart restates them in current dollars based on GDP. A press release on November 16, 2015 from the Association of National Advertisers reported that research sponsored by them found that advertising alone contributed 19% to the U.S. GDP in 2014, or $3.4 trillion.

How much of these percentages or dollars can be attributed just to either storytelling or public speaking? Back in 2002 Stephen Denning published an article in the RSA Journal titled How storytelling ignites action in knowledge-era organizations in which he guessed storytelling made up two-thirds of persuasion. Then on page xvi of his 2005 book The Leader’s Guide to Storytelling he said it conservatively was at least half of persuasion.  In their 2014 book Business Storytelling for Dummies Karen Dietz and Lori Silverman mention Denning’s 2005 book and link to Antioch’s article.

What about public speaking? Page 324 in Chapter 15 of Stephen Lucas’s book The Art of Public Speaking (10th edition, 2008) just mentions the 26% persuasion estimate as being from a Wall Street Journal version of a January 10, 1995 Associated Press article about McCloskey and Klamer by Amanda Bennett titled Economists + Meeting A Zillion Causes and Effects. If Stephen Denning can guess a half for storytelling, than I can take a wild guess of a fifth for persuasive public speaking, and come up with the dollar estimates shown above in a third bar chart. So, it might be over $912 billion!