I am pleased to report on the exceptional results that our organization produced in 2018, delivering over $11 million in Underwriting gain and representing one of the most profitable years we have experienced in over a decade, continuing upon a three-year trend of strong profit and growth.
Total in-force policy count increased to over 170,000, with the addition of over $32 million in new business, driving an increase in premium across all lines of business and in all states of more than 9%. Policyholder retention increased and over 26,000 new policies were added, demonstrating both agent and customer loyalty to our organization and satisfaction with the future direction of the Company.
Surplus grew to a new high of over $325 million showing that, with our 2017 affiliation to Auto-Owners, we have the financial capacity to support growth in premium and policy count for years to come.
I am also happy to share that A.M. Best upgraded Concord Group's Long-Term Issuer Credit rating to "a+" and affirmed our "A" Excellent Financial Strength rating, in recognition of the continued performance and financial strength outlined above.
Our affiliation with Auto-Owners Insurance Company continues to yield positive benefits to the organization by providing us with substantially broader product offerings, data analytics, and expense management capabilities. Along these lines, Life, Flood and Pet Insurance products were launched throughout the year. Commercial business appetite was broadened, and the Massachusetts Homeowners product was expanded to drive greater selectivity and competitiveness in these marketplaces.
Finally, a fundamental part of our culture is to give back to the communities in which we live and work, helping those less fortunate than ourselves. To this extent, I want to take a brief moment to recognize the contributions our employees and company have made both financially and in personal time to organizations like Granite State United Way, New Hampshire Historical Society, and various Food Banks and Family Support organizations throughout Northern New England, especially over the holidays.
Special thanks to our Employees and local Independent Agents for their hard work and effort, as well as our Directors and Policyholders for their support throughout 2018. We look forward to yet another year of profit, growth, and expansion in 2019.