The Trump administration has expanded its push for financial deregulation, with the Securities and Exchange Commission proposing two major changes to how publicly traded companies report their finances. The first would let companies file earnings reports only twice a year instead of quarterly, ending a rule that has existed for more than half a century. The second would exempt most companies the S.E.C. regulates from having to bring in outside auditors to verify internal books and processes for avoiding errors and fraud.

The rollback would weaken regulations passed by Congress in 2002, after the collapse of Enron and the implosion of Arthur Andersen revealed how easily companies could hide financial problems without independent oversight. Simon Johnson, a Nobel laureate economist and co-chairman of the Systemic Risk Council at the CFA Institute, warned: "If the quality of reporting information from the financial system deteriorates, then that absolutely leads to financial-sector risks of the kind that have bitten us before, as in 2008 and other crises."

Trump administration officials argue onerous regulations have made going public less attractive. Paul Atkins, the Trump-appointed S.E.C. chairman, said: "As part of my 'make I.P.O.s great again' agenda, we're advancing a modernized regulatory framework." The S.E.C. wants to bump the share of companies operating under lighter rules to about 80 percent from 50 percent, exempting them from the more thorough independent audits required under the Sarbanes-Oxley Act of 2002.

The Business Roundtable has supported the moves, but a broad range of former and current executives have criticized them. The S.E.C. received a lopsided response to the semiannual reporting proposal during its formal public comment period.