What portion of the stock market is now from margin buys?

There is no "link" that you can use that would show this information

No one agency tracks whether a purchase is made using margin since it is not a required piece of information when executed transactions ae reported. Only the executing broker needs to record the type of account used to execute the trade it is not important for the trade reporting or clearing.

SIAC at one point in time tried to gather this Information but many brokerage firms did not feel it was important to provide such data. And it is not important to any firm other than the firm carrying the account.

And why would that be worthwhile for someone to document so you could read it.

Edit: That information on the 1929 crash was compiled after the event to rationalize what had happened, there is no on-going monitoring of margin use that I am aware of. Margin rules were not well understood back then and times were good so people treated it as though it was free money.

You are wise to not use margin often....try to reduce "rarely" to "never"...it allows you to sleep bettre at night during bad times. I have a margin account but it is there simply to bridge a 5 day transaction processing period that occasionally comes into play. In tax deferred accounts margin (in Canada anyway) is not allowed and I have not difficulty managing my account.

Anyone that abuses margin deserves the trouble they may ultimately encounter...playing with fire IMHO

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