The year is nearing its end, and now's a good opportunity to look at what happened throughout 2012 to the stocks you follow. If you know the important things a company achieved, as well as any challenges it failed to overcome, then you can make a better decision about whether it really deserves a spot in your portfolio.

Today, I'll look at 3M (MMM 0.86%). As a member of the Dow Jones Industrials (^DJI 0.56%), the company best known for Post-it Notes has had a long history of innovation in a wide range of products. This year was no different, as 3M made strides toward more firmly establishing its strength across the industries it serves. Read on to find more on what moved shares of 3M in 2012.

Stats on 3M

Year-to-date stock return

16.2%

Market cap

$64 billion

Total revenue, trailing 12 months

$29.6 billion

Net income, trailing 12 months

$4.41 billion

1-year revenue growth

1.3%

1-year normalized earnings growth

3.5%

Dividend yield

2.5%

CAPS rating

*****

Source: S&P Capital IQ.

Why has 3M done so well in 2012?
Much of 3M's comes from its diversity. As a conglomerate, 3M has its fingers in everything from the consumer products so many are familiar with to dental supplies, specialized films for a variety of consumer goods, and its budding electronics and energy segment. Yet unlike General Electric (GE -3.19%), whose industrial businesses don't have all that much in common with segments like GE Capital, 3M's array of ventures fits together pretty well.

Recently, though, 3M's slowing growth has caused some to question whether the company is still innovative. But with a new chief executive onboard, Fool contributor Travis Hoium recently opined that CEO Inge Thulin could be the one to get 3M's research and development engines firing again.

In addition, 3M may turn more to acquisitions for growth. Although its attempt to buy Avery Dennison's (AVY 1.06%) consumer-products division failed, the recent purchase of Ceradyne has already promised to broaden 3M's product lines in a number of promising areas involving Ceradyne's ceramic materials, including defense.

Still, the company has faced headwinds. 3M does extensive business in Europe, where economic conditions have deteriorated for some time. In addition, 3M faces the specter of a medical-device surtax that could hit its bottom line -- albeit not to the same extent as the ultra-specialized MAKO Surgical (MAKO.DL) and similarly health-focused peers.

3M has done well this year and has the tools to excel in the year to come as well. With a good dividend, the key to 3M's success will be restarting growth.

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