Michael J. Sewell
Chief Financial Officer, Executive Vice President and Treasurer at Cincinnati Financial
Thank you, Steve, and thanks to all of you for joining us today.
Investment income continued to grow, up 10% for the second quarter of 2024 compared with the same quarter in 2023. Dividend income was down 1% or $1 million for the quarter, primarily due to two unusual items that totaled approximately $2 million. One was a holding with a June ex-dividend date in 2023 that moved to July 1st in 2024. The other was a holding that reduced its dividend rate by 53% after a spin-off transaction. Bond interest income grew 18% for the second quarter of this year. We again added fixed maturity securities to our investment portfolio with net purchases totaling $771 million for the first six months of the year.
The second quarter pre-tax average yield of 4.64% for the fixed maturity portfolio was up 30 basis points compared with last year. The average pre-tax yield for the total of purchased taxable and tax-exempt bonds during the second quarter of 2024 was 6.06%. Valuation changes in aggregate for the second quarter of 2024 were favorable for our equity portfolio and unfavorable for our bond portfolio. Before tax effects, the net gain was $149 million for the equity portfolio, partially offset by a net loss of $93 million for the bond portfolio.
At the end of the quarter, total investment portfolio net appreciated value was approximately $6.7 billion. The equity portfolio was in a net gain position of $7.4 billion, while the fixed maturity portfolio was in a net loss position of $700 million. Cash flow continued to benefit investment income in addition to higher bond yields. Cash flow from operating activities for the first six months of 2024 was $1.1 billion, up 33% from a year ago.
I'll move on to expense management, where we always work to balance controlling expenses with making strategic investments in our business. The second quarter 2024 property casualty underwriting expense ratio was 0.5 percentage points higher than last year, reflecting higher levels of profit-sharing commissions for agencies and employee-related expenses.
Next, let me comment on loss reserves, where our approach remains consistent and aims for net amounts in the upper half of the actuarially estimated range of net loss and loss expense reserves. As we do each quarter, we consider new information, such as paid losses and case reserves. Then, we updated estimated ultimate losses and loss expenses by accident year and line of business.
For the first six months of 2024, our net addition to property casualty loss and loss expense reserves was $578 million, including $506 million for the IBNR portion. During the second quarter, we experienced $40 million of property casualty net favorable reserve development on prior accident years that benefited the combined ratio by 1.9 percentage points.
The commercial line segment saw overall favorable reserve development of $29 million, driven by workers' compensation and commercial property, which more than offset the unfavorable development in commercial casualty. Commercial casualty was again the line of business having the largest amount of unfavorable reserve development, with a total of $28 million for the quarter, or less than 1% of that line's year-end 2023 reserve balance.
We released reserves in some recent accident years and added reserves totaling $51 million in aggregate for accident years prior to 2021, including $30 million for 2018 through 2020, due to case-incurred losses emerging at amounts higher than we expected. The unfavorable amounts reflects our slowing the release of IBNR reserves for some of those older accident years while adding to others.
On an all-lines basis by accident year, net reserve development for the first six months of 2024 included favorable $269 million for 2023, favorable $36 million for 2022, favorable $17 million for 2021, and an unfavorable $182 million in aggregate for accident years prior to 2021, with commercial casualty representing $167 million of the unfavorable $182 million.
I'll conclude my comments with the capital management highlights, another area where we have a consistent long-term approach. We paid $125 million in dividends to shareholders during the second quarter of 2024. We also repurchased 395,000 shares at an average price per share of $116.33. We think our financial flexibility and our financial strength are both in excellent shape. Parent company cash and marketable securities at quarter end was nearly $5 billion. Debt to total capital contributed continued to be under 10%, and our quarter end book value was at a record high, $81.79 per share, with $12.8 billion of GAAP consolidated shareholders' equity providing plenty of capacity for profitable growth of our insurance operations.
Now I'll turn the call back over to Steve.