There’s a beer in this for you. A glass of rosé from Provence if you prefer.

What’s the most liquid stock in the US market?

Let’s lay the groundwork. Stock exchanges describe market quality as low spreads. Spreads have never been tighter, they say, and costs for trading were never lower.

Heck, you can trade for free. That’s about as inexpensive as it gets. So, is a low-cost, low-spread stock market a quality and liquid place?

Depends what you mean. The market doesn’t fail often. Yes, we’ve recorded nearly 13,000 volatility halts since Mar 9. Remember all the marketwide pauses that month? Still, it didn’t quit operating.

The Nasdaq just corrected – dropped 10% – in three days. And rebounded as fast. It highlights the importance of the definition of “quality.”

Which leads back to liquidity, and by extension, volatility. All three words ending in “y” are related.

Let’s begin with what liquidity is not. Volume. Liquidity, bluntly, is the amount of a thing that will trade before the price changes. Put an offer on a house. What’s the spread between the price you’d pay, and the last that somebody else paid?

I’ve just debunked the idea that low spreads reflect quality. For the seller, a high spread is a reflection of quality.

Low spreads help parties with short horizons. If my investment horizon is 250 milliseconds, a spread of a penny is wildly attractive. How many pennies can I make, in how many different issues, every quarter-second?

But if my horizon is more than a day, a wider spread reflects higher quality. How come stock exchanges don’t mention that?

Let’s go one step further. To me, the measures we traditionally look to for guidance about market quality need revamping. For instance, beta, a measure of volatility, has the same flaws as our current economic measures of inflation. Beta measures how a stock moves from close to close in relation to the market.

Terrible measure of market quality. WMT, for instance has a beta score of 0.19, 20% of the volatility of the market. Yet its intraday volatility the past 20 days is 2.9%. The S&P 500 is 2.7% volatile over the same time (intraday high and low).

WHEN an investor buys during the day could in theory be nearly 3% different from somebody else’s price. And WMT, contradicting beta, is not a fifth as volatile as the market but 7% more volatile.

The truth is low spreads PROMOTE frequent price-changes, which is the definition of volatility. The parties driving low trading spreads are ensuring volatility. Creating it. And telling us it signals market quality.

They mean well. But good intentions pave roads to oblivion.

(Editorial note: Inflation isn’t the rate at which prices increase. It’s whether you can buy things. All over the economy, people now buy on credit. Debt has exploded. That’s the evidence of inflation. Not the Fed’s equivalent of beta.)

And liquidity isn’t volume. That’s confusing busy with productive. Volume is stuff changing hands. Liquidity is how MUCH of it changes hands. The most liquid stock in the market is AMZN (not counting BRK.A, a unique equity), at $70,000 per trade.

The mean component of the S&P 500 trades about $17,000 at a time. But here’s the kicker. Just 50 companies, 10% of the index, trade MORE than $17,000 per trade. That’s the list from AMZN to DPZ. Everybody else trades less.

Including now, AAPL. It used to be in the top ten. Now it’s 146th post-split, trading about $12,000 per transaction on average. TSLA was top five but post-split is now 49th at $17,600, well behind 32nd-ranked MSFT at $20,100.

Splits don’t foster liquidity. They breed volume. And price-changes. Volatility. We’re not anti-split. We’re anti-volatility, which increases risk for investors and the cost of capital for companies.