Exchange-traded funds offer a convenient way to invest in sectors or niches that interest you. If you'd like to add some mid-cap companies to your portfolio because they're small enough to have significant room for growth and large enough to have executed their strategy well in past years, the WisdomTree MidCap Earnings ETF
ETFs often sport lower expense ratios than their mutual fund cousins. The WisdomTree ETF's expense ratio -- its annual fee -- is a relatively low 0.38%. The fund is fairly small, too, so if you're thinking of buying, beware of occasionally large spreads between its bid and ask prices. Consider using a limit order if you want to buy in.
This ETF has performed rather well, topping the S&P 500 over the past three and five years. As with most investments, of course, we can't expect outstanding performances in every quarter or year. Investors with conviction need to wait for their holdings to deliver.
With a low turnover rate of 18%, this fund isn't frantically and frequently rejiggering its holdings, as many funds do.
What's in it?
It's been a rough time for the overall market over the past few years, and the past few months have erased many recent gains. (Fortunately, for most of us, it's the long run that matters.) Whirlpool
Falling about 11% was American Capital
The big picture
A well-chosen ETF can grant you instant diversification across any industry or group of companies -- and make investing in and profiting from it that much easier.
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Longtime Fool contributor Selena Maranjian, whom you can follow on Twitter, holds no position in any company mentioned. Click here to see her holdings and a short bio. The Motley Fool has a disclosure policy.