Thanks very much, Kevin. As Kevin said, I'm here with Sarah Doran, who's our Chief Financial Officer; and Bob Myron, our Chief Operating Officer, and we're looking forward to answering your questions in a minute. Before we do that, we'd like to set the stage with a few observations about our quarter and about market conditions in general.
This is one of the most favorable markets I've witnessed in 30 years. The E&S business, which is at the core of our franchise is growing with more policies in force substantially higher rates and lower loss cost. We wrote 28% more E&S premium this quarter than in the prior year. New submissions were up by 9% in E&S and renewal submissions were up 27%.
The increase in renewal submissions is an indication that standard companies continue to retrench and are not seeking to move accounts from the E&S market to the standard market. We're selective underwriters and 8 of our 12 E&S underwriting divisions grew. Trailing 12-month Core E&S premium is $615 million, a 91% increase over the same period just 2 years ago.
We continue to be able to get more rate per unit of exposure. This last quarter was the 15th quarter in a row, we've reported significant rate increases. In 8 of these 15 quarters, renewal rate increases on our E&S business have been greater than 5%. In every quarter this year, rates were up over 10%, and this quarter, rates were up 12.8%. An already hard market continues to gain strength.
Year-to-date, our policies in force have increased by 26%. And while we're growing both premium and policy, claims counts in Core E&S are down 15% this quarter compared to 2019. In the most recent months, claims frequency has been dropping rather precipitously. New claims count within E&S were down 18% in April, 31% in May, 15% in June, 11% in July, 23% in August and 9% in September and 32% through mid-October.
This drop in claims count is all the more notable as we have more policies in force than in prior years and earned premium from Core E&S is increasing. Core E&S claims counts per $1 million in earned premium through the third quarter are 30% lower than the 3-year average between 2017 and 2019. So obviously, these trends bode very well for the future.
Our fully developed core E&S loss and LAE ratio from 2003 through 2017 is 54.4%. We're carrying the 2018 through 2020 years at a 65.5% loss in LAE ratio. Our calendar year paid and reported loss ratios in Core E&S is 24% on a [ 0.5% ] reported through 3 quarters. These are among the lowest reported and paid ratios since 2005.
Our expense ratio is 24.8% this quarter, down from over 30% in the first quarter. Sarah will speak in a moment about -- more about this positive trend in expenses. So we reported a combined ratio of 85.2% for the E&S division after adding approximately $10 million to reserves for the runoff of the large commercial account canceled at the end of last year. We raised reserves in the runoff book because in September, we observed a spike in medical cost.
This unexpected rise in cost seems to be the result of people with non-life-threatening injuries, having postponed surgeries and inpatient treatments due to concerns about being in a hospital or a surgical clinic during the pandemic. We continue to close claims rapidly in this runoff book. And as of quarter end, we've closed slightly more than half the claims outstanding at December 31, 2019.
And at this point, we have roughly 2% of the open claims that we ever received from the commercial auto accounts. So this is moving out rapidly. Our growing -- our rapidly growing and very well-priced book of E&S premium can absorb spikes in the runoff costs while still delivering very strong returns to shareholders and maintaining our 65.5% loss in LAE ratio from 2018 to 2020.
In this quarter, we were particularly glad that our focus on casualty business allowed us to avoid significant exposure to, or losses from, the very difficult hurricane season work or from COVID-19 losses. At the same time, the large industry losses from these events will tend to reinforce the attractive pricing we're benefiting from.
Our specialty admitted segment is also gaining traction. Third quarter gross written premiums were 12.1% higher than a year ago. We've added 8 new programs within the segment over the course of 2020. Three of these new programs have already added $15.4 million in gross premiums through 3 quarters. And many others are just beginning to produce premiums and fee income, and we enjoyed a 22.8% increase in fee income in the first 3 quarters.
Our net retention of gross written premiums in our specialty admitted segment is under 15%. We're developing partnerships in which while we retain some risk to align our interest with reinsurers, we're focused on earning fee income.
Year-to-date, our return on equity in the specialty admitted segment is in the low double digits. Having developed our sea legs in this division, we're directing our marketing efforts towards larger fronting programs, we believe the margins from this business, already good, can still improve.
Within the specialty admitted segment, we've reduced net written premiums from workers' compensation policies by about 1/3 as we feel pricing in that area of the market is a little soft. In our Reinsurance Division, we wrote $91 million in gross written premiums through 9 months, which was a 21% reduction compared to last year. Some of that reduction is only a timing difference as the renewal moved from the third to the fourth quarter.
The reinsurance segment has reported 102.1% combined ratio for the quarter. Pricing in this segment is improving, and our internal study show renewal rate increases, including changes in terms and conditions of 4.3%, 6.4%, and 8.7% in 2018, 2019 and year-to-date 2020, respectively.
I'd now like to address some important and very good news for our company. We announced last evening that Frank D'Orazio, formerly the Chief Operating Officer and Chief of Staff to the CEO with Allied World, will become CEO of James River next Week. Some of you will recall that I retired previously and returned in August of 2019.
Our company is in a very good position, thanks to the hard work of all my colleagues. We are in a rising market, and it really seemed to me that this was a good time to introduce a new CEO who can make the transition when we are enjoying great momentum.
The board conducted a very broad search. And attracted many highly qualified candidates. I'm very pleased Frank will be taking the helm. I suspect some of you may all -- on this call may already know him. He has tremendous depth as an executive, having run large profitable insurance operations in the U.S. and from Bermuda.
His management style and experience fit our culture. He's an underwriter by training, and he has a long history of building successful underwriting businesses. He is keenly aware of the opportunity the hard market presents.
Frank and our team have already begun to work on the transition. I will remain as non-executive Chair of the Board and look forward to supporting Frank and his executive team. I have no doubt we are in very good hands. I anticipate over time under Frank's leadership and with the support of the terrific James River team, we will become even more profitable and demonstrate more capabilities than we do today.
And with that, let me turn the call over to Sarah.