Piper Jaffray technical analyst Craig Johnson, who correctly forecast the stock rally of the past two years, thinks the good times will keep rolling — maybe for nearly another decade.

While the S&P 500 has slid 4 percent from its July 24 record high, "these selloffs burn themselves out," he told MarketWatch. "The secular bull market is just starting."

The bull market began in 2009, and if it resembles the ones of the 1950s and 1980s, it could last until 2023, Johnson said.

Editor’s Note: 5 Shocking Reasons the Dow Will Hit 60,000

He said that investors made five times their money after 1952 and 15 times their money from 1982 to 2000. If the S&P 500 rose five times from its 2009 low, it would reach 3,335. And if it rose 15 times, it would hit 10,005.

The index stood at 1909.57 at Thursday's close.

A strong economy and strong earnings could be the catalyst for further gains, Johnson said. "Things are definitely getting better with the economy."

To be sure, he acknowledged that "we’re overdue for a true correction." The S&P 500 hasn't dropped 10 percent since October 2011.

CNBC contributor Ron Insana, also a long-term bull, thinks the current correction will continue.

"I still believe the market remains vulnerable to a decline of 5 to 10 percent or more . . . within the context of a secular bull market," he wrote on CNBC.com. "As a consequence, I still own puts on the S&P 500, with a strike price of 1,850, expiring in September."

Editor’s Note: 5 Shocking Reasons the Dow Will Hit 60,000

Related Articles:

• Blackstone's Wien: 'This Is a Correction in an Ongoing Bull Market'
• Mark Hulbert: Dow Theory Doesn't Signal Stock Selloff