On Aug. 24, the power band on Wall Street flickered: a plunge of almost 1,000 points in the early morning hours on the New York Stock Exchange. By the end of the day, the Dow Jones closed down nearly 600 points after shares took a historic roller coaster ride. Prior to the opening bell, the Dow had never lost more than 800 points in one day.

Apple helped the market do a turnaround, and Wall Street has since recovered around 800 points with stability in the Chinese market. But the big drop did some damage. Many stocks are still recovering.

A look at the long haul

Advisors usually tell investors not to panic when the market takes a dive; it will make a rebound, they say. Try to look at an investment portfolio as a long-term proposition – how will the stock fare over six months, a year, maybe longer?

If you had bought stocks like Apple, Google, Target, and Home Depot at the beginning of the year, you would have some winners and losers. Google would have given you a 20% return on your investment; Home Depot, around 12% – even after the big plunge of Aug. 24. Wal-mart Stores, however, took a 24% dive in year-to-date returns. Microsoft and Delta would also have delivered you a negative return.

And how have renal stocks fared since the beginning of the year? Fresenius Medical Care AG has offered a moderate return so far in 2015; Rockwell International has delivered a near 20% return. Other companies have had a more difficult time (see Table 1).

 Table 1

Some of these companies that have had a poor year-to-date performance do offer dividends to investors. That helps lessen the hurt. But the key to good investing, experts say, is diversify: make sure your portfolio covers a wide range of companies. That can include some renal stocks, but keep an eye on their quarterly reports so you know which stocks make the best investment.