The Latham, N.Y., company also offered earnings estimates for the first and second quarters.
Plug Power had said in March that it had discovered mistakes in its past earnings reports.
It recently traded at $24.78, up 13%. It has dropped 65% in the past three months amid concern about the stock's valuation and the earnings issues.
But it’s still up by a factor of more than five over the past 12 months, thanks to investor enthusiasm for hydrogen and other renewable energy.
Plug said the restatements had no effect on its cash position, business operations or economics of its commercial arrangements.
The changes cut a dime from 2020 earnings per share and 3 cents from 2018 EPS.
The company still expects to reach gross billings targets of $475 million for all of 2021, $750 million in 2022 and $1.7 billion in 2024.
Analysts Martin Malloy of Johnson Rice and Pearce Hammond of Piper Sandler said the restatement completion is a positive. Malloy has a buy rating and Hammond a neutral rating.
TheStreet.com Founder Jim Cramer offered a mixed take on Plug last month. "If you believe in hydrogen power, then Plug is the winner,” he said. "I don't like those accounting issues, though. Any accounting irregularity equals sell."
Also in April, Morgan Stanley analysts resumed coverage of the hydrogen fuel cell producer with an equal-weight rating on valuation concern. Stephen Byrd set a $35 price target on the company.