The Beginner’s Guide to Investing

Warren Buffett suggests you read this 19th century poem when the market is tanking

Warren Buffett, Chairman and CEO of Berkshire Hathaway.
Adam Jeffery | CNBC

The stock market has had a volatile year, and it's not over yet: The Dow Jones Industrial Average lost more than 520 points on Monday and the fell 2.1 percent. Both are in correction and on pace for their worst December performance since the Great Depression in 1931.

But for the average person, shifts in the market, even ones as dramatic as the ones we've seen this year, shouldn't be cause for panic. During times of volatility, seasoned investor Warren Buffett says it's best to stay calm and stick to the basics, meaning, buy-and-hold for the long term.

So, during downturns, "heed these lines" from the classic 19th century Rudyard Kipling poem "If—" which help illustrate this lesson, Buffett wrote in his 2017 Berkshire Hathaway shareholder letter:

If you can keep your head when all about you are losing theirs ...
If you can wait and not be tired by waiting ...
If you can think – and not make thoughts your aim ...
If you can trust yourself when all men doubt you ...
Yours is the Earth and everything that's in it.

Market downturns are inevitable, Buffett pointed out, using his own company as an example: "Berkshire, itself, provides some vivid examples of how price randomness in the short term can obscure long-term growth in value. For the last 53 years, the company has built value by reinvesting its earnings and letting compound interest work its magic. Year by year, we have moved forward. Yet Berkshire shares have suffered four truly major dips."

He went on to cite each of the steep share-price drops, including the most recent one from September 2008 to March 2009, when Berkshire shares plummeted 50.7 percent.

Major declines have happened before and are going to happen again, he says: "No one can tell you when these will happen. The light can at any time go from green to red without pausing at yellow."

Rather than watch the market closely and panic, keep a level head. Market downturns "offer extraordinary opportunities to those who are not handicapped by debt," he says, which brings up another important investing lesson: Never borrow money to buy stocks.

"There is simply no telling how far stocks can fall in a short period," writes Buffett. "Even if your borrowings are small and your positions aren't immediately threatened by the plunging market, your mind may well become rattled by scary headlines and breathless commentary. And an unsettled mind will not make good decisions."

Don't miss: Warren Buffett and Ray Dalio agree on what to do when the stock market tanks

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