Thank you, Jonathan. During the quarter ended September 30, 2021, the U.S. loan market modestly strengthened versus the quarter ended June 30, 2021. U.S. loan prices, as defined by the S&P/LSTA Leveraged Loan Index increased from 98.37% of par as of June 30 to 98.62% of par as of September 30. According to LCD, during the quarter, BB-rated loan prices increased 13 basis points, single B-rated loan prices increased 4 basis points and CCC-rated loan prices increased 26 basis points on average.
The 12-month trailing default rate for the S&P/LSTA Leveraged Loan Index decreased to 35 basis points by principal inbound at the end of the quarter after starting the quarter at 1.25%. Note that this rate is just 14 basis points above the post-global financial crisis low.
Additionally, the distress ratio, defined as a percentage of loans with a price of below 80% of par, ended the quarter at approximately 70 -- [ 0.72% ], the lowest level in nearly 7 years and below levels seen in June of 2020. During the quarter, the increase in loans -- U.S. loan prices led to an increase in U.S. CLO equity net asset value.
According to Wells Fargo, during the quarter, the median U.S. CLO equity NAV modestly improved from approximately 59% of par to approximately 61% of par, while the median over collateralization cushion increased from 354 basis points to 373 basis points.
Additionally, according to Wells Fargo, the loan pools within CLO portfolios generally maintained their weighted average spreads at 340 basis points compared to 341 basis points the previous quarter as heavier supply in the loan market continued to weigh on spreads.
Issuance in the CLO primary market continues at a historical place. Year-to-date, through September 30, approximately $130 billion of new issued deals had priced in the primary market compared to the prior full year record of $129 billion set in 2018. And approximately $191 billion of refinancings and resets in price in the primary market compared to the prior full year record of $167 billion set in 2017. Oxford Lane was able to take advantage of the strength in the primary market this quarter, does make 9 new issue CLO equity investments, refinancing 5 deals to lower the cost of debt financing of those deals and resetting 2 deals.
As a function of our activity in the primary market this quarter, we were able to lengthen the weighted average reinvestment period of Oxford Lane's CLO equity portfolio from September of 2023 to March of 2024.
From a trading perspective, we had one of our busiest quarters to date, as Jonathan mentioned. We were able to source investments in both the primary and secondary markets, with over 50% of our purchases in the primary market on a market value basis.
In the current market environment, we intend to continue to utilize an opportunistic and unconstrained CLO investment strategy across U.S. CLO equity, debt and warehouses, as we look to maximize our long-term total return. And as a permanent capital vehicle, we have historically been able to take a longer-term view towards our investment strategy.
With that, I will turn the call back over to Jonathan.