Volatile commodity prices, supply risks and political/regulatory developments are the top concerns of U.S. producers, and the threat of bankruptcy has reached a six-year high, according to BDO USA LLP.

BDO’s 2016 Oil and Gas RiskFactor Report issued on Tuesday also highlights how damaging the oil price rout has been to the industry. Of the top 100 exploration and production (E&P) companies ranked in a September 2015 index, about 10% either have declared bankruptcy, been acquired or were delisted from U.S. stock exchanges. Additionally, the threat of bankruptcy more than doubled in risk factor reporting year/year, from 8% in 2015 to 19%, the highest level in six years.

“When oil prices first began to decline in mid-2014, many energy industry observers hoped that the slump would follow the pattern of the 2008 contraction which, though painful, was brief,” said BDO Partner Charles Dewhurst, who leads the natural resources practice. “But we’re now well beyond that possibility, and the time has come for the sector to remove its rose-colored glasses.

“This downturn will stay with us for a while,” but it also offers opportunities for savvy operators “to streamline operations and position themselves for success further down the line.”

BDO used the most recent U.S. Security and Exchange Commission Form 10-K filings of the 100 largest (by assets) publicly traded U.S. E&Ps for its sixth annualreport to examine the most listed risk factors.

Besides a tie for the top three risks — prices, supply and political — the top concerns cited by the largest E&Ps included disruptions for natural disasters (97%); operational/E&P (96%); environmental/health regulations (96%); limited access to capital/indebtedness (96%); inaccurate reserves estimates (93%); general national/global economic conditions (89%); general competition (87%); terrorist/civil unrest (85%); impact of climate change/greenhouse gas legislation (85%); hydraulic fracturing regulation (84%); changes in demand levels (84%); and maintaining adequacy/effectiveness of internal controls, financial reporting and accounting standards (84%).

Also cited were risks from uninsured liabilities (83%); liabilities/costs for pollution resulting from operations (83%); shortage of rigs/equipment/personnel (81%); use of hedging/derivative instruments exposing company to financial risks (80%); and competition from alternative energy sources (79%).

E&Ps face a “wave of financial challenges,” BDO found.

Increases in the cost of operating declined as a risk, down to 59% from 70% in 2015, but “it is clear that these lower costs are not enough to offset the concurrent decline in revenues caused by the price slump,” researchers said. “Financial challenges have also affected companies’ exposure to accounting-related risks. As prices dropped throughout 2015, many companies were forced to write down the carrying value of a number of their properties, leading 84% of companies analyzed to specifically note risks associated with financial reporting, accounting methods and impairment this year.”

A “significant” and growing worry is the threat posed by cyberattacks. Risks associated with data breaches grew from 12% in 2012 to 74% this year, “with cybersecurity proving to be a rapidly moving target as bad actors evolve and seek to leverage increasingly sophisticated hacking methods.”

Regulatory concerns also persist as major risks. E&Ps also cited changes to tax policies, with 70% noting this as a risk.

“Most recently, significant uncertainty has surrounded the Obama administration’s proposal to levy a $10.25 tax per barrel of oil,” researchers said. Of the companies that mentioned tax changes broadly in their 10-Ks, one-third specifically cited the new proposal as a growing concern.

“Even in flush years, the oil and gas industry needed to remain vigilant about potential changes to their tax liabilities,” said BDO’s Clark Sackschewsky, tax principal. “But with prices as low as they are, the prospect of an additional tax, which, at this point, would substantially raise U.S. producers’ breakeven price, could prove highly destabilizing as the sector looks to get back on its feet.”