When you've been approved for margin stock trading, you're also eligible to short stock. Almost every successful stock trader has shorted stock at one time or another. When you short stock, you make money when the company's shares fall—or, even better yet, when they crash. The problem is that you can expose yourself to unlimited liability when you do this.
During its latest rebalance, the Invesco S&P 500 Momentum ETF (SPMO) halved its exposure to the tech sector from 36.6% to 17.2%, and more than doubled the weight in health care to 27.9%. Utilities and real estate went from nearly zero to 11.7% and 7.1% of the portfolios, respectively. That helps explain the fund’s moderate loss of 1.7% in May, even though the tech stocks within the S&P 500 slumped a much steeper 5.7%.
The solution to both is investing in stock index funds and ETFs. While mutual funds might require a $1,000 minimum or more, index fund minimums tend to be lower (and ETFs are purchased for a share price that could be lower still). Two brokers, Fidelity and Charles Schwab, offer index funds with no minimum at all. Index funds also cure the diversification issue because they hold many different stocks within a single fund.
Barchart calculates a custom index (the Barchart Market Momentum Index) which is used as an indicator of overall change in the markets. The index reflects the movement of more established stocks: those with SEC filings, with 6 months of trading activity, and with price above $2.00. A high value means the market is moving up, where as a negative value implies the market is down today.