There have been so many factors influencing the market's twists and turns now that it's easy to lose count.
Let's, however, take a look at seven that seem to be the most prevalent influences of the rapid-fire price action lately.
1. Price discovery
The notion that the marketplace actually can find a rational price, absent the influence of meddling central bankers, seems almost quaint. But we could be in the beginning stages of true price discovery as the Federal Reserve keeps the monetary printing presses shut down and prepares, at some point, to normalize interest rates.
Following the market correction that put the 12.5 percent off its 52-week high, the index's price-earnings ratio has fallen into line with historical norms near 16. In short, the market may finally have come to grips with the notion that in an economy struggling to grow more than 2 percent, a multiple of 18 is a little expensive.
Couple that with a market that hasn't corrected in nearly four years, and you've got some key ingredients for volatility.
"What I think we're seeing is a typical late-stage bull market in which there are precious few shock absorbers for the market to withstand even a modest negative impact," said Scott Clemons, chief investment strategist at Brown Brothers Harriman. "When something happens, the market reaction is going to be magnified."
2. The Fed
Fed actions seem like low-hanging fruit at this point, but the logic is hard to dispute.
The S&P 500 had gained more than 7 percent from Jan. 1, 2014, until Oct. 29, which was the day the U.S. central bank ended the third round of quantitative easing, a monthly bond-buying program that swelled the Fed's balance sheet to $4.5 trillion and jacked up the stock market index by nearly 200 percent.
Since the end of QE3? The market's down about 4 percent. Pretty simple, maybe too simple, but hard to ignore.
China's economy is in flux, and central planners are desperately trying to use policy to soothe market fears that the nation is heading into a deep and prolonged slowdown.
In keeping with point No. 1 here, China spooked a fragile market that might, at less lofty valuations, have been able to withstand a growth shock to the world's second-largest economy.
"Recent developments in China simply catalyzed a much-needed and overdue valuation correction in the U.S. stock market," S&P Capital IQ analysts Michael G. Thompson and Robert A. Kaiser said in a note. "To be sure, investors need to be concerned with market liquidity issues, anticipated corporate earnings growth and China's economy, but the market correction witnessed this past week was a necessary valuation correction that simply needed a catalyst."
What China leads to on a longer-term basis is hard to gauge, though some perspective is probably in order.
"The real broader view here is this is a natural correction in a broader bull market, not indicative of a broader recession," Liz Ann Sonders, chief investment strategist at Charles Schwab, said in an interview. "In terms of the averages, we've had much sharper corrections inside the market at the industry level, the individual company level. You can't just look at what the averages are telling you."
4. Massive late-day sell orders
Get ready to add "market on close" to your lexicon.
It's mostly a trader's term referring to an order that has to be placed before 3:45 p.m. ET, allowing the trader to buy or sell a stock on close that the initiator believes could move after hours.
On most days, there are imbalances either to the buy or sell side that could nudge the market's close in one direction or the other. However, on Tuesday, there was an avalanche of sell orders that took a more than 400 point rally in the Dow Jones industrial average and sent it plummeting to a 205 point loss by the time the closing bell rang.
The sell imbalance reportedly amounted to $3.5 billion, which is the largest since at least 2009 and perhaps the biggest ever, according to Morgan Stanley.
If fund investors continue to get jittery and want to sell at the bell, expect to hear a lot more about "MOC" orders.
5. The computers
As the Dow cascaded lower by more than 1,000 points at Monday's open, "circuit breakers" that halt trading if shares drop at rapid rates had to shift plunge protection into overdrive, as more than 1,200 issues were affected.
One of the main issues was a series of "flash crashes" in which exchange-traded funds fell below their net asset values and various shares also collapsed beyond anything that fundamentals would suggest. Market participants were quick to fault the machines that have nearly taken over trading.
"The algos were definitely taking control of the market," Peter Costa, head of Empire Executions, said of the algorithms that dictate high-frequency trading. "The market tanked and it tanked with such speeding velocity that there were no humans involved. It was a completely computer-driven movement."
6. Technical breakdowns
This kind of market is a chart watchers dream.
Techincal analysts have been finding all kinds of formations justifying the recent selloff, from "sell" signals under Dow Theory to Elliott Wave analysis that, according to Walter Zimmerman, chief technical analyst at United-ICAP, is "the most perfect pattern I have ever seen in any market at any time."
Zimmerman was referring specifically to a "diagonal triangle fifth wave."
You don't need to know what that means. What you do need to know is that it is a bearish chart formation indicating a rough time ahead for the market. Zimmerman said it had been coming together for a long time.
"This was probably the most well-announced collapse in the history of the market, because it took so long for the topping action to complete itself," he said. "It took yards of patience (to wait for the pattern to be completed), but that patience was rewarded."
7. More China
This is a little sketchy, but market chatter also has focused on Chinese troop movements along the North Korean border over the past few days.
Depending on the source, China either has been trying to intimidate North Korea into ending tensions on the peninsula, or simply mobilizing troops in just-in-case mode.
Regardless, the movements were one on a laundry list of causes that contributed to Tuesday's last-hour meltdown.
"Geostrat (Bob Hardy's blog) sources report rumors of PLA armored columns moving towards Beijing Military Districts from northeast," Jeff Saut, chief market strategist at Raymond James, said in his morning note to clients. "These troops could be those that were deployed over the weekend in Yanji city on the North Korean border on August 23-24. But, those units were from Shenyang Military District in the northeast, and they have not been invited to the Beijing September 3 military parade. So far these are just rumors."