.....Regardless, for a long time the biggest question in my mind was not how passive flows drive markets higher. It was what happens if those flows slow or reverse.
Most retirement contributions come directly from paychecks. That means the passive bid is ultimately tied to employment. If fewer people are working, fewer contributions go into retirement plans. And if people start pulling money out, whether due to unemployment, financial stress, or emergencies, those funds must eventually sell assets to meet withdrawals.
That is where things get interesting.
In an interview last year, I pointed out how market analyst Mike Green laid out the mechanics of how a passive driven market could unwind. His thesis is simple but unsettling. Passive funds behave like systematic trading programs. When money flows in they buy. When money flows out they sell. Unlike traditional active managers, passive funds maintain almost no cash buffers. They are designed to remain fully invested. That means redemptions require selling into the market.
In a market where passive vehicles now represent more than half of US equity ownership, that dynamic could create structural fragility. Green’s broader point is that passive investing has fundamentally changed how markets behave.
Historically, stock markets were supposed to discount the future. Investors would anticipate recessions or slowdowns before they happened. But if flows dominate price formation, markets may no longer react to economic risks until the flows themselves change. And since those flows are tied to employment, the market may not respond to a downturn until jobs actually start disappearing.
At that point the feedback loop could become destabilizing.
Less employment means fewer contributions. Fewer contributions mean less passive buying. Withdrawals could mean forced selling. If the marginal buyer disappears at the same time sellers emerge, liquidity could vanish quickly.
