The markets ended the year on an up note, but not all stocks fared well, especially ones in the pharmaceutical and energy sectors. Here's a list of the worst performing stocks listed on the NYSE and the NASDAQ as of December 15, 2016.

NYSE

Valeant Pharma (VRX) – Down 88.05%

2016 wasn’t an easy year for Valeant. After struggling with allegations of fraud, the company got a new CEO and cleaned up its act by revamping operations and paying off its massive debt, but the stock has been hammered nonetheless. Until recently, hedge fund investor Bill Ackman had been trying allay fears about the stock, but even his fund Pershing Square recently sold some of its holdings at a loss.

Stone Energy Corp.(SGY): Down 85.43%

The oil exploration company has been in trouble due to low crude prices and a series of bad losses, which have forced it to the brink of bankruptcy. The stock that began its year trading around $43 is now priced at close $6.

Adeptus Health (ADPT): Down 85.07%

One of the country’s largest operators of freestanding emergency rooms saw its stock lose pulse when it delayed announcing its third quarter earnings. That uncertainty combined with less than expected second quarter earnings hammered the stock. The share price high for the year was close to $71 in May but the stock currently trades around $8..

Compagnie Generale De Gephysqu (CGG): Down 75.37%

The company provides support and reservoir capabilities, especially to oil and gas exploration companies. Sluggish activity in the space due to low oil prices has not only hurt the company financials but has also made the stock slip.

Halcon Resources (HK): Down 34.41%

Another company adversely impacted by falling crude prices. The oil explorer had been struggling with large amounts of debt but reached a restructuring agreement with lenders in May of this year. The agreement included filing for Chapter 11 bankruptcy and that news made the share price drop. Even though the company is now out of Chapter 11 and $1.8 billion of debt has been erased from its books, the stock is yet to recover completely. Analysts also warn that the company is still highly leveraged.

NASDAQ

Dryships Inc.(DRYS): Down 97.88%

A slowdown in the shipping sector caused big problems for the Dryships and its stock has been on a steady downward path since the beginning of the year. The company tried to prop the stock up by going ahead with no less than three reverse stock splits this year. A revival in the Baltic Dry Index saw the stock pick up slightly in November before trending back down again.

SAexploration Holdings (SAEX): Down 97.25%

Yet another casualty of low crude prices. The company that collects and provides seismic data to oil & gas explorers has seen sluggish demand that has hurt its financials.

Skyline Medical (SKLN): Down 95.43%

The company’s stock plummeted in February when it extended its deadline for investors to buy newer stock units in exchange for older ones. Fear that reluctance of investors to convert could mean there’s something wrong with the company spelled doom for the share price which dropped to under a dollar in March and remained there until October. The threat of de-listing forced the company to implement a reverse stock split and the stock now trades close to $3.

Concordia International: Down 94.71%

The specialty pharma company too has struggled with less than expected earnings in the year but the big reason for the drop in its share price is the news some big-ticket investors pulled out of the running to pick up a strategic stake in the company. It began 2016 trading at close to $40/sh but it currently languishing at just a little over $2/sh.

Ophthotech Corp.(OPHT): Down 93.81%

Biotech firm specializing in drugs to treat eye diseases was having a decent year stock-wise until December when the news of disappointing results of two phase 3 clinical trials caused the stock price to plummet over the course of a single weekend from around $38 on December 9 to $6.24 on December 12.

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