For Plug Power (PLUG -5.26%) investors, the wait is over. The company announced that it has finalized the restatement of its financial reports for 2018 and 2019 as well as quarterly filings for 2019 and 2020; in addition, Plug Power has filed its 2020 annual report. According to the company, there were several areas that it needed to revisit, including (but not limited to) the book value of assets, lease liabilities, and impairment charges of long-lived assets.

Breaking a trend of growing revenue for several years in a row, Plug Power reported 2020 net revenue of negative $93 million, while restated net revenue for 2019 and 2018 was $230 million and $174 million, respectively. Management primarily attributes the sharp decline in 2020 net revenue to a rise in the vesting of stock warrants related to Amazon.

The stark contrast in the financial performance of 2020 compared to previous years wasn't limited to the top line. Plug Power reported a loss per share of $1.69 -- steeper than the losses per share of $0.36 in 2019 and $0.39 for 2018. Management credits the wider loss in 2020 to $41.4 million in noncash charges related to loss accrual provisions and asset impairments.

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While the company's financial performance in 2020 represents a decline from the previous years, management remained optimistic. In the first quarter of 2021, for example, management expects to report $70 million in gross billings, which would represent a 60% year-over-year increase; moreover, it expects to report $105 million in gross billings for the second quarter. If successful in meeting second-quarter guidance, it will represent a 50% increase over the same period in 2020. Looking further out, management reaffirmed its gross billings targets of $475 million in 2021, $750 million in 2022, and $1.7 billion in 2024.