Howard Widra
Analyst · RBC Capital Markets
Thanks, Elizabeth. Good afternoon, and thank you for joining us today. I'll begin my remarks with an overview of the quarter, and we'll then provide some additional business highlights. Following my remarks, Tanner will discuss the market environment, review our investment activity for the quarter and provide an update on credit quality. Greg will then review our financial results in greater detail. We'll then open the call for questions.
Over the last several years, we have built a well-diversified portfolio of true first lien floating rate corporate loan invested in less cyclical industries with granular position sizes. Our ability to coinvest with other funds and entities managed by Apollo, including MidCap, allows AINV to participate in larger deals while maintaining relatively small hold sizes on our balance sheet. As you know, MidCap is the hub of Apollo's middle market direct origination business and is on par with any lender in the marketplace.
The overall MidCap direct origination platform was very active during the period, closing approximately $7.7 billion in new commitments during the quarter and $19.6 billion in commitments in 2021. The MidCap platform provides AINV with access to a wide funnel of opportunities, which allows us to be selective and find attractive investments.
After market close today, we reported net investment income for the December quarter of $0.35 per share. Results for the quarter benefited from strong fee and prepayment income and reflect operating with average net leverage in the middle of our target leverage range. We ended the period with net asset value per share of $16.08, up $0.01 per share.
Our corporate lending portfolio, Merx, had net gains during the quarter. The corporate lending portfolio continues to improve, which Tanner will discuss later during the call. Results for December also reflect the benefit from the monetization of non-earning and under-earning assets and redeploying those proceeds into our core strategies. We have consistently generated cash from our noncore assets, and we are focused on executing some more significant progress in the coming quarters.
During the December quarter, we received repayments of approximately $10 million from 3 of our noncore positions, 2 of which were nonearning, which included $4 million from 1 position without any reduction in NAV and $2 million from 1 investment which was $2 million above fair value. We also received approximately $29 million from the repayment of second lien position. Post quarter end, Dynamic Product Tankers, one of our shipping investments, closed on the sale of 3 ships, which will be generating an additional $18 million in cash proceeds at our December 31st NAV in the March quarter.
We have visibility into additional monetizations from our noncore portfolio in the coming quarters, and we look forward to reporting our continued progress. Pro forma for the Dynamic sale, noncore assets represent only 6% of AINV's total investment portfolio. Second liens represented only 5% of the corporate lending portfolio at the end of December. Lastly, we repurchased stock during the period, a meaningful discount to NAV, which was accretive to NAV per share and moderately accretive to net income per share.
Moving on to other business highlights. Our Board has increased our share repurchase authorization by $25 million, having nearly completed our existing authorization. We obviously hope opportunities to repurchase our share at a meaningful discount to NAV do not occur. But when they do, this authorization will allow us to create value for our shareholders.
Turning to our distribution. For the quarter, the Board has declared a base distribution of $0.31 per share and a supplemental distribution of $0.05 per share. Both distributions are payable on April 7, 2022, to shareholders of record as of March 21, 2022. As a reminder, the dividends being declared today are the last of the dividends that we previously indicated would be maintained at $0.31 for the base distribution and $0.05 for the supplemental distribution.
One of our objectives is to provide greater visibility for our shareholders with respect to the distribution. So for the next 2 quarters, we intend to declare a base dividend of $0.31 per share plus a supplemental dividend in an amount such that the base and supplemental combined will equal the prior quarter's net investment income per share. This means that next quarter, we expect to declare a base dividend of $0.31 plus a supplemental dividend of $0.04 or $0.35 in total, which is equivalent to the NII per share for the December quarter.
We expect to have greater clarity in the coming quarters regarding the timing of the embedded upside in our portfolio and the impact of interest rates on our earnings.
With that, I'll turn the call over to Tanner to discuss the market environment and our investment activity.