Oct 28, 2026, 3:33 PM ETInterview, Fireside Chat

Dimensional’s David Booth on How to Interpret Risk and 'Stay Calm' Amid Uncertainty

Before the 1960s, lack of quality research data prevented testing investment hypotheses; the development of CRISP data transformed investing into a testable science.
Six decades of testing have largely failed to demonstrate that professional money management justifies its costs due to the difficulty of separating skill from luck.
Only a negligible number of managers can consistently beat the market, making it statistically impossible to identify them in advance.
Long-term equity returns have averaged 10.2% over the past century, representing a 6% risk premium over risk-free assets.
Booth attributes this persistent return not to a fixed risk factor, but to "human ingenuity," where entrepreneurs innovate during bad economic scenarios to restore growth.
The 2020 pandemic recession lasted only one quarter, illustrating the market's rapid recovery when investors remain exposed to equities rather than timing exits.
Missing a single 20% market recovery requires a 40% gain to return to break-even, as there are no "mulligans" or do-overs in long-term compounding.
Buying the broad market allows investors to participate in the upside of human ingenuity rather than betting on specific future winners or losers.
Uncertainty creates optionality and opportunity; eliminating uncertainty would imply a riskless rate of return for all assets, stifling progress.

Uninvested capital suffers from the erosion of purchasing power; an uninvested $15,000 held by Booth's parents lost 80% of its value over 40 years.
Had that same capital been invested in the market, it would have grown to over $1 million, demonstrating the "magic of compounding."
Wealth accumulation is the result of the compounding of many decisions made over time, with no shortcuts available.
Investors should plan rather than predict, as the future is inherently unpredictable and few could anticipate major global shifts two decades prior.
True wealth is linked to optimism and clarity of values, such as family, which allows individuals to feel wealthy even without significant assets.
A high school teacher's intervention to encourage a student who failed a calculus placement test had a profound long-term career impact, highlighting the value of belief in others.
The most effective approach to uncertainty is to be flexible and adaptive over the long haul rather than attempting to control immediate outcomes.

Dimensional Fund Advisors grew from $50 billion in assets under management (AUM) in 2003 to over $1 trillion in recent years.
Leadership strategy involved setting an aspirational goal of $500 billion in AUM to accelerate internal conversations, even if the timeline was not strictly fixed.
The firm pivoted from exclusively serving large institutional pension funds to targeting Registered Investment Advisors (RIAs), which now account for more than two-thirds of assets.
Access to Dimensional funds for RIAs was initially restricted to ensure quality, requiring advisors to attend "Dimensional Boot Camp" seminars to ensure they understood the long-term strategy.
This "exclusive" access model created a sense of pride among advisors, which served as an effective marketing strategy for RIA adoption.
Hiring criteria prioritize team players who believe in the firm's evidence-based philosophy over ego, as excessive trading is incompatible with the firm's model.
The firm distinguishes between investing (buying the market) and gambling/prediction markets (like sports betting), noting that while the latter is acceptable for a portion of assets, it is not the right strategy for the core portfolio.
Growth is driven by a culture that prizes evidence over ego, ensuring that all employees align with the long-term view of market mechanics.