WASHINGTON — President Donald Trump has celebrated his regulatory rollbacks as one of the biggest triumphs of his first year in office.

While he’s struggled for legislative wins — the passage of the GOP tax bill being the only major exception — his administration has wielded the executive branch's authority to shape scores of federal rules and reverse Obama-era policies on everything from climate change to campus sexual assault. He boasted in a speech at the White House in mid-December that his administration had eliminated 22 old regulations for every new one it had issued.

By certain measures, Trump has overstated his success. Fully eliminating rules that are already on the books is typically a time-consuming and onerous process. Instead, his administration has focused on stopping or delaying proposed regulations that have yet to take effect, and many of these rules are still being developed or weren’t poised to take effect anyway, as Bloomberg News reported recently. Federal courts have also curtailed some of Trump’s major deregulatory efforts.

That said, Trump has made progress in halting or slowing some major Obama-era initiatives. And some regulatory experts believe that the message the president is sending on deregulation is just as important as any specific policy changes he is enacting.

"This is the most anti-regulatory administration — probably even more so than the early Reagan administration — since regulations became a policy issue," said Stuart Shapiro, a Rutgers University professor who studies regulatory policy.

Here are some of the Trump administration’s most significant deregulatory actions in 2017:

Worked to eliminate the Clean Power Plan

In October, the Environmental Protection Agency announced that it would eliminate the centerpiece of Obama’s climate-change strategy. In 2015, the Obama administration finalized the Clean Power Plan, which sought to reduce power-sector emissions by 32 percent by 2030, relative to 2005 levels. The plan required states to hit certain emissions targets in order to cut greenhouse gases, reducing the country’s reliance on fossil fuels and boosting clean-energy sources. EPA chief Scott Pruitt said that repealing the measure meant that "the war against coal is over."

The Supreme Court had already halted the plan after legal challenges by a group of states and industry stakeholders, and a federal appeals court is reviewing the measure. Meanwhile, the EPA said it is moving to rescind the plan and replace it with an alternative.

Killed net neutrality

In mid-December, the Federal Communications Commission voted along party lines to eliminate rules requiring internet service providers (ISPs) to treat all internet traffic equally. The Obama-era rules prohibited ISPs from blocking or slowing down access to specific websites, or charging more for paid "fast lanes." (Comcast, the parent company of NBC News, said shortly before the vote that it has not paid for fast lanes or prioritize internet traffic, and has "no plans to do so.")

While the FCC is an independent agency, Trump named Ajit Pai as its chairman shortly after taking office in January. Pai criticized the net neutrality rules as unnecessary impediments to innovation and competition that would ultimately hurt consumers. The agency’s controversial vote has already prompted a fierce backlash: Democrats have vowed to reinstate net neutrality through congressional procedure, while New York’s attorney general said he would take the lead in suing on behalf of several states to block the decision.

Delayed a methane rule

Trump’s Interior Department delayed a rule to limit methane emissions from oil and gas operations on federal lands, pushing back implementation until 2019. The Obama rule had aimed to cut down on leaks, and the venting and flaring of methane gas, which has increased with the rise of hydraulic fracturing. Methane makes up 10 percent of greenhouse gas emissions and is a more powerful pollutant than carbon dioxide.

Federal courts had blocked Trump’s earlier attempt to stop the methane rule, and a congressional push to stop the rule fell short this year. But the administration has continued to persist in its efforts to halt the measure, which the fossil-fuel industry has criticized as unnecessary and burdensome.

Revoked guidance on campus sexual assault

In September, the Education Department rescinded Obama’s guidelines for addressing sexual assault on college campuses under Title IX, which prohibits discrimination by sex in any federally funded education program. The Obama administration had instructed colleges to use a "preponderance of evidence" when evaluating sexual assault cases.

Trump’s education secretary, Betsy DeVos, said that standard was unfair.

"Schools have been compelled by Washington to enforce ambiguous and incredibly broad definitions of assault and harassment," she said in September, adding that "if everything is harassment, then nothing is."

Instead, the Education Department has told institutions to use a standard of “clear and convincing evidence” in sexual assault cases.

Used Congress to overturn Obama-era rules

With the Trump administration’s support, the Republican-controlled Congress killed more than a dozen Obama-era regulations by using an obscure legislative tool known as the Congressional Review Act. The procedure gives Congress 60 legislative working days to overturn a rule after it is published in the Federal Register.

The White House and Congress used the act to nullify rules that Obama imposed in the last days of his administration: They overturned new limits on gun sales to those with severe mental illness; undid requirements for employers to keep records on workplace injuries and illnesses for five years; and repealed restrictions on internet service providers’ ability to use and sell personal data, including web-browsing history, among other regulatory changes.

Trump and Congress used the same tool to kill a new regulation that would have made it easier for consumers to band together in class-action lawsuits against financial firms, restricting the use of forced arbitration clauses. The Consumer Financial Protection Bureau, an independent agency, put out the rule in July under the leadership of Obama appointee Richard Cordray, who left the agency in late November.