During the quarter, we earned GAAP net income of $158 million.
However, the purchase market remains strong and accounted for nearly 90% of the $28.7 billion of new business we wrote in the third quarter.
This level of new business writings combined with a higher annual persistency, resulted in our insurance in force increasing 2.4% to $268 billion, nearly 12% higher than last year.
Reflecting the continued strength of the housing market, purchase applications in our application pipeline, the leading indicator of NIW, continue to account for more than 85% of applications received in recent months.
Taking a look at our in-force portfolio, our loss ratio was a low 8.1% in the quarter.
At quarter end, the excess of our PMIERs available assets over the minimum required assets increased by $300 million to $2.6 billion, and our PMIER sufficiency ratio was 180% at the end of the third quarter.
We executed on this strategy during the quarter by writing $28.7 billion of new business and by returning nearly $180 million to shareholders through the repurchase of 10 million shares and paying the increased common stock dividend.
In the third quarter, we earned $158 million of net income or $0.46 per diluted share and generated an annualized 13% return on beginning shareholders' equity.
Adjusted net operating income was $157 million compared to $150 million in the third quarter last year.
During the quarter, total revenues were $296 million, the same as last year.
The net premium yield for the third quarter was 38.4 basis points, which was down 7/10 of basis point compared to last quarter.
During the quarter, they were $17 million, which was flat to last quarter but down from $32 million in the third quarter of 2020.
Net losses incurred were $21 million in the third quarter compared to $29 million last quarter and $41 million in the third quarter last year.
In the quarter, we received approximately 9,900 new delinquency notices, which represents less than 90 basis points of the number of loans insured as of the start of the quarter and drove the low loss ratio of 8.1%.
As a point of comparison, in the third quarter of 2019 before the onset of the COVID-19 pandemic, we received approximately 42% more new delinquency notices and they represented approximately 140 basis points of the number of loans insured at the beginning of that quarter, while the loss ratio in the third quarter of 2019 was 12.7%.
These positive credit trends continued in October, their notice inventory declining by another 1,500 notices as Cures continue to outpace new notices.
The estimated claim rate on new notices received in the third quarter of 2021 was approximately 7.5% compared to approximately 8% in the third quarter of 2020.
In the quarter, we realized $18 million of favorable loss reserve development compared to immaterial development last quarter and in the third quarter of last year.
Primary paid claims in the quarter were $18 million compared to $11 million last quarter.
As Tim mentioned, in the third quarter, we paid an $0.08 per share dividend for a total of $27 million and repurchased 10 million shares for a total of $150 million.
In October, we repurchased an additional 3.8 million shares for a total of $60 million under a 10b5-1 plan, we put in place earlier this year.
The Board also authorized an additional $500 million share repurchase program that expires at the end of 2023.
And as previously announced, the Board declared an $0.08 per share dividend payable on November 23.
At the end of the third quarter, we had $716 million of holding company liquidity and a $2.6 billion access to the PMIERs minimum requirements at the operating company.
MGIC's access to the PMIERs requirements as of September 30 resulted in a PMIERs sufficiency ratio of 180% and remained above our current target level.
As of October 30 -- as of October 31, 2021, our holding company's liquidity also remains above our current target levels even if we fully use the remaining $81 million on the share repurchase authorization that expires at year-end 2021.
At this time, our plan is to use those additional dividends if they are received to settle the eventual redemption of our 9% Convertible Junior Debentures due in 2063.
Our most recent 10-K has additional details, but under the terms of the debentures, we can redeem the debentures for principal plus accrued interest when our share price closes above a certain level for 20 of 30 consecutive trading days.
For 2021, that share price level is $17.20.
We hope to provide a redemption notice for the debentures in the near term with the redemption date at least 30 days later.
While the timing remains uncertain, retiring the debentures would eliminate approximately 16 million potentially dilutive shares and $19 million in annual interest expense.
And would reduce our debt-to-capital ratio by approximately 300 basis points as of September 30 on a pro forma basis.
The housing market remains strong, and we have a book of business that has solid underwriting credit characteristics, which is supported by a strong and dynamic balance sheet with a low debt-to-capital ratio, an investment portfolio of nearly $7 billion, contractual premium flow and a robust reinsurance program.

Summary:
In the third quarter, we earned $158 million of net income or $0.46 per diluted share and generated an annualized 13% return on beginning shareholders' equity.