We had net proceeds from vessel sales of $5.3 million in 2020, $18.7 million in 2019 and $29.7 million in 2018. We last raised equity capital in 2014, through three registered common stock offerings with net proceeds of approximately $112.3 million. Our principal use of funds has been to acquire our vessels, maintain the quality of our vessels, service our debt and fund working capital requirements, as well as to repurchase shares of our common stock.
Our liquidity needs, as of December 31, 2020 through the end of 2021, primarily relate to scheduled debt repayments, funding expenses for operating our vessels, general and administrative expenses as well as to committed capital expenditures and any vessel acquisitions we elect to make either independently or in collaboration with a third party investor. As of December 31, 2020, our committed capital expenditures consisted of the delivery installment amounting to $23.2 million for the 11,000 cbm LPG carrier newbuilding that was delivered in February 2021. The construction cost of this vessel was partially financed by a bank loan amounting to $18.9 million. Furthermore, we have nine scheduled drydockings for 2021, the costs of which are anticipated to be covered from our operating cash flows, while we do not have material expenditure requirements for water ballast system installations.
As of December 31, 2020, our aggregate debt outstanding, net of deferred finance charges, was $351.8 million, of which $40.5 million was classified as a current liability.
We believe our internally generated cash flows will be sufficient to fund our operations, including working capital requirements, for at least 12 months taking into account our existing capital commitments and debt service requirements, as well as the expected impact of the
COVID-19
pandemic on the global economy and our business which could however, be even more severe than currently anticipated.
For a description of our credit facilities please refer to the discussion under the heading “—Credit Facilities” below.
Our dividend policy and stock repurchases will also affect our liquidity position. See “Item 8. Financial Information—Dividend Policy.” On May 23, 2019, we publicly announced that our Board of Directors authorized the repurchase of up to $10,000,000 of shares of our common stock. As of March 31, 2020, 900,702 shares of common stock had been repurchased for an aggregate of $2.8 million (excluding commissions), with the average purchase price of $3.16 per share.
No repurchases have been made under this program since March 2020.
In April 2020, we repurchased a total of 1,366,045 shares of our common stock through a tender offer, which was announced on March 31, 2020, at a price of $2.10 per share, for a total cost of $2.9 million, excluding fees and expenses. We had also repurchased, under a prior repurchase program, $20.3 million of shares of common stock from 2014 through
mid-2016.
Net cash provided by operating activities—was $52.1 million for the year ended December 31, 2020, $30.8 million for the year ended December 31, 2019 and $37.8 million for the year ended December 31, 2018. This represents the net amount of cash, after expenses, generated by chartering our vessels. Net cash provided by operating activities increased in 2020 compared to 2019, mainly due to the increase in our profitability, and due to lower outflow of payments to Stealth Maritime in 2020 compared to year 2019.
Net cash (used in)/provided by investing activities—was an outflow of $58.1 million in 2020, while net cash provided by investing activities was $33.5 million for the year ended December 31, 2019 and net cash used in investing activities was $78.6 million for the year ended December 31, 2018.
In 2020, we acquired two small newbuilding LPG vessels, the
and the
for $44.0 million, sold two of our older vessels, the
and
each for further trading with net sale proceeds of $5.3 million, and acquired through our JV arrangement established in early 2020 and in which