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 stocks to your portfolio because they're big enough to have proved themselves to some degree and yet small enough to still have lots of room to grow, and you also favor seemingly undervalued stocks, the Vanguard Mid-Cap Value ETF
ETFs often sport lower expense ratios than their mutual fund cousins. The Vanguard ETF's expense ratio -- its annual fee -- is an extremely low 0.10%. (Vanguard is known for low fees.)
This ETF has performed reasonably, 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.
What's in it?
Lots of mid-cap companies had strong performances over the past year. Hard-drive storage specialist Seagate Technology
Regional bank Regions Financial
Mortgage REIT American Capital Agency
Even Delta Air Lines
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.
Longtime Fool contributor Selena Maranjian, whom you can follow on Twitter, holds no position in any company mentioned. Check out her holdings and a short bio. The Motley Fool owns shares of Wells Fargo. Motley Fool newsletter services have recommended buying shares of Wells Fargo. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. Try any of our Foolish newsletter services free for 30 days. The Motley Fool has a disclosure policy.