Misdiagnosing The Risk Of Margin Debt

This past week, Mark Hulbert wrote an article discussing the recent drop in margin debt. To wit:

“Plunging margin debt may not doom the bull market after all, reports to the contrary notwithstanding.

Margin debt is the total amount investors borrow to purchase stocks, which historically has risen during bull markets and fallen during bear markets. This total fell more than 6% in October, according to a report last week from FINRA. We won’t know the November total until later in December, though I wouldn’t be surprised if it falls even further.

A number of the bearish advisers I monitor are basing their pessimism at least in part on this plunge in margin. It’s easy to see why: October’s sharp drop brought margin debt below its 12-month moving average. (See accompanying chart.)”

“According to research conducted in the 1970s by Norman Fosback, then the president of the Institute for Econometric Research, there is an 85% probability that a bull market is in progress when margin debt is above its 12-month moving average, in contrast to just a 41% probability when it’s below.

Why, then, do I suggest not becoming overly pessimistic? For several reasons:

1) The margin debt indicator issues many false signals2) There is insufficient data3) Margin debt is a strong coincident indicator.”

I disagree with Mark on several points.

First, margin debt is not a technical indicator which can be used to trade markets. Margin debt is the “gasoline,” which as Mark correctly states, drives markets higher as the leverage provides for the additional purchasing power of assets. However, that “leverage” also works in reverse as it provides the accelerant for larger declines as lenders “force” the sale of assets to cover credit lines without regard to the borrower’s position.

That last sentence is the most important. The issue with margin debt, in particular, is that the unwinding of leverage is NOT at the investor’s discretion. It is at the discretion of the broker-dealers that extended that leverage in the first place. (In other words, if you don’t sell to cover, the broker-dealer will do it for you.) When lenders fear they may not be able to recoup their credit-lines, they force the borrower to either put in more cash or sell assets to cover the debt. The problem is that “margin calls” generally happen all at once as falling asset prices impact all lenders simultaneously.