The bull market in US stocks just celebrated its sixth birthday, yet there’s good reason to think this rally will continue.

Since the 2008 financial crisis, the Nasdaq Composite has outperformed the broad stock market, as the rising ratio of the Nasdaq to the New York Stock Exchange (NYSE) shows:

The Nasdaq is at a crossroads, but the signs point to a breakout. The Russell 2000—a leading indicator of the overall equity market—just broke out of a year-long consolidation, while the S&P 500 continues to test record highs. The NYSE is also at a similar inflection point.

This bull market may seem to be running on borrowed time. However, the technical picture reminds us that no one can accurately predict the duration or the extent of a bull market.