So FINRA has finally decided to warn brokers to warn their customers about leveraged ETFs. I covered this subject a long time ago. Back then, I noted that the math will never add up. It can’t. For these funds to work as people expect them beyond a day, the leverage would have to be some multiple of the logarithm of the price change, not a multiple of the percent price change. It’s a subtle difference, but over a period of more than a day, it makes a gigantic impact.