An additional note is that along with the riskbof this strategy comes costs. The broker/dealer will charge you an interest in the margin. Therefore, you must consider that this will reduce your returns whether you have gains or losses. It also makes the amount average cost of your investment increase over time which would require a higher price to breakeven. The Fed has facilitated this risk taking strategy as they have maintained interest rates lower but this can unwind as you mention given the expected continued rise in interest rates. Great post!