Market Milestone: 9 Years, 5 Months, 13 Days

Dot-com bubble, eat your heart out: The S&P 500 has marked its longest-running bull market ever by going 3,454 days since hitting a low point in March 2009, the Wall Street Journal reports. Despite inching down a point Wednesday to 2,861, per the AP, the storied blue-chip index has ballooned more than 400% in price terms since 2009 and continues to hover near the record-high closing of 2,872 set in January. Driven by a variety of factors—like President Trump's tax cut and advances in US technology companies like Apple, Alphabet, and Amazon—the market is belying skeptics who said China's slowdown and rising US interest rates would de-horn the bull. "Companies are tearing it up," says an analyst. For more:

• The real record: The term "bull market" refers to a rally that climbs more than 20% without ever dropping by 20%, notes Bloomberg. The last rally went from 1990-2000, but really the market only slid 19.92% in 1990, so you could say that rally started in 1987 and remains the longest ever. All depends on whether you round up.

• Another gripe: The S&P fell 22% on an intraday basis between May and October 2011, but always ended the trading day in better shape—which kept the bull run going. "There is a lot of sloppy data or historical revisionism or both," says a Hulbert Financial Digest editor of Wednesday's record. "People just blithely assume that that bull market started on March 9, 2009. Depending on who you talk to, there have been one or two bear markets that occurred in that period."
• Naysayer: With the record comes predictions that it's destined to end soon. Jim Paulsen, chief investment strategist at Leuthold Group, tells CNBC that five key factors—valuations, investor confidence, rising company profits, low competition from other investments, and an economic recovery—may have peaked. "It's not any one of those, per se, but it's the fact that all of them are fairly used up." Plus, unemployment is about as low as it can get, and low unemployment has historically coincided with lower market return, he says.
• Possible risks: Strategist Andrew Milligan says US equities will keep running strong next year, but tells the Guardian that "there are risks. The Fed could tighten too much, China could lose control of its debt problems, or Italian bonds could cause another sovereign debt crisis."
• Defies expectation: This bull market also behaves unlike previous rallies, the AP notes. Trading volume has been low and fewer companies are selling stock in IPOs, for example. There have also been nail-biting developments such as Trump's trade battles, a US credit downgrade, and near-collapse of the eurozone, but investors went right back to buying. "I don't think anyone could have predicted the length and strength of this bull market," says a JP Morgan strategist.
• Fell so far: Others say the market is only high because the 2008 financial crash brought it so low. "That has caused interest rates and the Fed to be so much more accommodative for so much longer than other bull markets that it has helped to elongate it," a Smead Capital Management officer tells the Financial Times. Similarly, an equities chief calls it "the most hated bull market of all time" because of the monetary stimulus. "No one has ever wanted to believe in it."
• Terminology: In case you wondered, one explanation for the term "bull market" is that a bull thrusts up with its horns, while a bear attacks down with its claws.

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