Shares of Netflix (NASDAQ:NFLX) plunged as much as 6.4% overnight. That's the second huge plunge in a row, adding up to 10.5% lost over the last two days. But this is perfectly normal for Netflix when we're winding up for another quarterly report.

Netflix is an extremely volatile stock in the days before earnings releases. Here's how the stock has oscillated in the last few trading days before each of the four latest earnings updates:

Data from Yahoo! Finance.

As you can see, Netflix shares tend to wriggle and squirm like a can of worms right before quarterly earnings reports. The overall trend is sometimes negative and sometimes positive, but more often mixed. The one thing all four of these quarters have in common is very simple: Netflix shares made several large moves -- in one direction or the other -- in the days leading up to each report.

The streaming-video maven is set to report third-quarter results again in about two weeks. It's not surprising to see the stock jumping or diving right now. That's particularly true given Netflix's massive gains in 2013, coupled with the debt-ceiling impasse pressuring nervous investors to take some profits right about now.

So, how has this boiling uncertainty worked out for Netflix investors in the past? I'm glad you asked:

Data from Yahoo! Finance.

The roiling seas of Wall Street have led Netflix investors to some epic next-day gains and equally huge losses once the actual numbers were known. Subscriber numbers shocked the Street twice in the last four reports and merely met expectations in the other two reports. The upcoming update could swing either way, depending on how the company's Emmy-winning series pulled their weight and how overseas markets responded to their large marketing and content budgets.

The stock could most certainly plunge on Oct. 22 if subscriber counts come in low. For your reference, Netflix guided to 31 million domestic accounts and 8.7 million international subscribers, give or take about 5%. Another large sell-off would open a tempting buy-in window. That's what happened a year ago, and the shares I bought then have soared 245% higher.

Whether Netflix sinks or soars this month, the tremendous long-term-growth story remains intact. If you're betting on a drop this time, don't forget to close your shorts and sell your put options before the holiday season's figures show up next January.

That's sure to be a painful mistake.

Fool contributor Anders Bylund owns shares of Netflix, but he holds no other position in any company mentioned. Check out Anders' bio and holdings or follow him on Twitter and Google+.

The Motley Fool owns shares of Netflix. Motley Fool newsletter services have recommended Netflix. The Motley Fool has a disclosure policy.

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