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The stock market had a good year in 2016, with double-digit percentage returns rewarding investors who stayed invested despite the aging bull market. Yet even though those gains are solid, they pale in comparison to the much larger increases in share prices that some individual stocks saw. In particular, Freeport-McMoRan (NYSE:FCX), SodaStream International (NASDAQ:SODA), and Array BioPharma (NASDAQ:ARRY) have all tripled in value over the past 12 months, and different factors led to their respective success. Let's look more closely at these three stocks to see why they tripled and whether any further gains are likely.

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Freeport enjoys a double bump

Freeport-McMoRan was the beneficiary of improving conditions in two key markets that it serves, and that's a big part of the reason behind its 250% rise over the past 12 months. The company has a long history of mining operations, and better conditions in commodity markets for both of its key mined products reassured investors who had suffered from severe losses in past years. In particular, copper prices gained on hopes for increased industrial activity, while gold and other precious metals performed well in bouncing back from big price declines since the early 2010s.

Meanwhile, Freeport also benefited from the rise in crude oil prices. Many had criticized Freeport's acquisitions of two oil and gas companies in 2013, which turned to be particularly ill timed in light of crude's subsequent plunge. Yet the bounce in oil means that Freeport should be able to avoid further impairment charges, and that could boost earnings and result in further growth if the energy market continues to behave well.

SodaStream fizzes higher

SodaStream International also gave investors a pop, rising 228%. The primary reason for the rebound was a revamping of the home-carbonator specialist's corporate strategy, moving away from an out-of-favor sector to concentrate on healthier fare.

In particular, SodaStream had initially hoped to corner the home soda market, offering an environmentally friendly way to make sugary carbonated soft drinks. Yet the company suffered when concern about health impacts of sugary beverages resulted in decreased demand for the SodaStream appliances and flavorings that drive much of its business. In response, SodaStream emphasized its ability to carbonate plain water, and that new marketing strategy has led to great success. If consumers keep seeing the value of on-demand seltzer water, then SodaStream could continue to climb.

Array looks healthier

Array BioPharma specializes in cancer-fighting treatments, and the biopharmaceutical company got good news last year from its drug development pipeline. The company applied to the U.S. Food and Drug Administration for approval of Array's binimetinib treatment for skin cancer, which showed evidence of dramatic improvement in survival versus traditional chemotherapy, and investors look forward to FDA consideration by mid-2017. More good news came from a combination study involving binimetinib and fellow drug encorafenib, and investors are hopeful that both will eventually gain FDA approval to fight melanoma, which has become increasingly common.

Looking ahead, Array has other prospects for growth. Its skin-cancer treatments show some promise in helping patients with colorectal cancer, which would open up a whole new target population for the company. At the same time, other candidate treatments also have the potential to produce impressive results of their own. Investors should watch Array closely in 2017 to see how its various drug programs proceed.

It's rare to see a stock triple in a single year, but these three stocks have beaten the odds. Turnaround stories like Freeport and SodaStream often build momentum that can last longer than one would think, and Array's prospects hinge on whether it can keep finding successful treatments with blockbuster potential.