The passcode you will need for both numbers is 4277895.
At January 1, we saw opportunities for profitable growth in both of our segments and across our platforms, resulting in the full deployment into our underwriting portfolio of the $1.1 billion raised last June.
As a result, in 2021, we expect to grow our net premiums written by approximately $1 billion and believe that we've materially increased the profitability of our underwriting book.
In a year, impacted by the global COVID-19 pandemic and multiple weather-related catastrophic losses, we grew book value per share by 15% and tangible book value per share plus change in accumulated dividends by 18%.
For the year, our return on equity was 11.7% and our operating return on equity was 0.2%.
In line with retaining more risk, we increased our ownership in DaVinci and Medici, and now have $1 billion co-invested in various joint ventures consistent with our strategy of strong alignment with our partners.
As I mentioned already, the result of this diligent planning and strong execution is that we now believe that we will grow net written premiums in 2021 by about $1 billion with an increase in expected profit.
Starting with our consolidated results and beginning with the fourth quarter where we reported an annualized return on average common equity of 10.9%, benefiting from mark-to-market gains in our strategic investment and fixed-income portfolios.
Annualized operating return on average common equity was negative 4.4%, primarily driven by weather-related losses in the COVID-19 pandemic.
We grew our book value per common share by $3.33 or 2.5% and tangible book value per common share plus change in accumulated dividends by $3.84 or 3%.
Net income for the quarter was a $190 million or $3.74 per diluted common share.
Reported an operating loss of $77 million or $1.59 per diluted common share.
This excludes $268 million of net realized and unrealized gains on investments and $23 million of net foreign exchange gains.
This includes an operating result with a net negative impact of $166 million from weather-related losses and $173 million from the COVID-19 pandemic.
Now moving on to the full year 2020, where we grew our book value per share by 14.9% and tangible book value per share plus change in accumulated dividends by 17.9%.
We reported a return on average common equity of 11.7% and an operating return on average common equity of 0.2%.
Net income for the year was $732 million or $15.31 per diluted common share and operating income was $15 million or $0.12 per diluted common share.
Included in this operating income was a net negative impact of $494 million from weather-related losses and $287 million from the COVID-19 pandemic.
While we reported underwriting losses of $152 million in the quarter driven predominantly by weather-related losses and COVID-19.
As I mentioned, weather-related losses had a $166 million net negative impact on our results for the quarter.
Of this, $100 million relates to events in the quarter as well as aggregate contracts.
The remaining $66 million was from continuing development on the Q3 2020 were the related catastrophe events.
The costliest storms for us in the fourth quarter were Hurricane Zeta and Delta, both of which made landfall in Louisiana as category 2 hurricanes and Hurricane Ada which made landfall in Florida as a tropical storm.
Additionally, Hurricanes Delta and Zeta chartered a similar path to Hurricane Laura with Delta making landfall within about 10 miles.
Now moving on to the $173 million net negative impact from COVID-19.
While we have not received a significant number of formal claim advisories to-date, the information that we obtained during the renewal process provided us with a reasonable basis to update our estimate of potential losses in category 3, which we refer to as the known-unknowns and includes business interruptions.
The majority of the COVID losses in the quarter related to category 3.
The net negative impact of COVID-19 for the year stands at $287 million and represents our best estimate based on information available of the aggregate impact of the pandemic on our business as a whole.
Moving now to our Property segment, where we grew gross written premiums by 26% in the fourth quarter and 23% in the year.
We reported a property combined ratio of 126% for the quarter and 99% for the year with COVID-19 and weather-related losses being significant drivers of our results.
Specifically, weather-related losses at 47 points to the property-combined ratio for the quarter and 35 points for the year.
COVID-19 added 46 points to the combined ratio for the quarter and 12 points for the year.
Our losses in the Property segment during the quarter were partially offset by 25 points of favorable development.
Now moving onto our casualty results, where the fourth quarter gross premiums written decreased by 5% in the quarter and grew by 18% in the year.
We continue to meaningfully grow our casualty business and our full-year growth rate of 18% is more indicative of our plans for this business going forward.
The combined ratio for casualty was 104% for both the quarter and the year.
These results were driven impart by the impact of COVID-19, which increased the combined ratio by 1.7 points in the quarter primarily in accident and health and 6 points for the year.
During the quarter, we also experienced 1.4 points of weather-related losses related primarily in the specialty lines.
For the year, weather-related losses had 8.8 impact on the casualty combined ratio.
Total fee income was $36 million for the quarter and $145 million for the year.
For the year, the net redeemable noncontrolling interest attributable to DaVinci, Medici and Vermeer was $231 million.
This represents a portion of our underwriting and investment income that we share with our joint venture partners, which is up 14% from 2019.
We reported strong investment results in the quarter and finished the year with total investment results of $1.2 billion.
This is comprised of $354 million in net investment income and mark-to-market gains of $821 million.
After adding materially to investment grade credit in the second quarter, we reduced this exposure by about 13% in the fourth quarter with an emphasis on shorter-dated maturities as credit spreads approach relatively tight levels.
The average duration of our managed portfolio was unchanged at 2.9 years, while the duration of the retained portfolio moved modestly lower in the fourth quarter to 3.6% of years.
At this point, I will provide additional information on our expenses in foreign exchange gains, and starting with the acquisition expense ratio was 23% for both the quarter and the year.
However, you will notice that there were some noise across the segments in the quarter, where the acquisition expense ratio declined 5 points in the Property segment against the comparable quarter.
For casualty, the acquisition expense ratio increased by 8 points against the comparable quarter.
Our direct expense ratio, which is the sum of our operational and corporate expenses divided by net premiums earned has continued to decline and was 6% for the quarter and 8% for the year.
At 2%, the corporate expense ratio was largely flat relative to the comparable quarter and year.
Corporate expenses did increase $3 million in the quarter.
However, this increase was driven by $7 million charge from the impairment of certain U.S. insurance licenses related to the restructuring of the TMR operating subsidiaries as well as non-recurring severance-related expense.
We also reported a $23 million foreign exchange gain in the quarter, approximately one-third of this gain relates to Medici and has no impact on our bottom-line, as it is backed out through noncontrolling interest.
As Kevin mentioned, we have had a very successful joint venture capital raise in preparation for the January renewal, raising over $700 million across DaVinci, Upsilon and Medici for 2021, and this includes $131 million of our own capital.
This is an addition to the $1 billion in capital that we raised across our various joint ventures in 2020, which also included $138 million of our own capital.
On top of these investments, we also purchased $117 million of DaVinci shares from third-party investors.
In aggregate, we have increased our stake in both DaVinci and Medici to 28.7% and 15.4% respectively.
As you recall, we initially recorded $104 million reserve primarily for category 1.
We also adjusted loss picks for category 2 exposures to reflect the likelihood of increased claim activity due to the pandemic and the resulting economic slowdowns.
We've now received enough information to update our COVID estimate, and this resulted in $173 million net negative impact for the quarter, primarily rated two property exposure in category 3.
We experienced a record 30 name storms, 12 of these made landfall in the U.S., six is hurricanes, including one major.
The previous record was in 1916 with nine land-falling storms.
About 50% of our property business renews at January 1st, and as I discussed, we had a very successful renewal.
With rates up 20% to 25%, we found many attractive opportunities to grow, both existing and new customers at January 1 renewal and believe that the market will continue to harden through 2021.
Our growth in traditional property cat was relatively muted, demand was flat with rate increases across the book averaging about 10%, with loss impacted U.S. business enjoying larger increases and non-loss impacted European business up single-digits.
While rates in the retro market were up 5% to 15%, as I discussed earlier, additional supply against suppressing rate increases as the renewal progressed.
That said, the retro market has experienced four consecutive years of rate enhancement, resulting in cumulative average rate increases approaching 50%, so while a little smaller, our retro book is attractive.
As a result, we will grow our gross written premiums in Casualty and Specialty for the year by approximately $500 million with lines like general liability and D&O being particularly attractive.
As Bob mentioned, including our own participation, we raised over $700 million across our joint venture vehicles.

Summary:
Net income for the quarter was a $190 million or $3.74 per diluted common share.
Reported an operating loss of $77 million or $1.59 per diluted common share.
During the quarter, we also experienced 1.4 points of weather-related losses related primarily in the specialty lines.