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Exhibit 99.1 SELECTIVE INSURANCE® Selective Reports Excellent First Quarter 2021 Results , Including Net Income of $ 1.77 per Diluted Common Share , Annualized Return on Common Equity ( " ROE " ) of 16.8 % , Non - GAAP Operating Income of $ 1.70 per Diluted Common Share , and a Non - GAAP Operating ROE¹ of 16.2 % In the first quarter of 2021 , we reported : • • • • Net premiums written ( " NPW " ) increased 23 % compared to the first quarter of 2020 ; GAAP combined ratio of 89.3 % ; After - tax net investment income of $ 56 million , up 24 % compared to the first quarter of 2020 ; and Book value per common share of $ 42.38 Branchville , NJ - April 28 , 2021 - Selective Insurance Group , Inc. ( NASDAQ : SIGI ) today reported financial results for the first quarter ended March 31 , 2021 , with net income per diluted common share of $ 1.77 and non - GAAP operating income¹ per diluted common share of $ 1.70 . " Our excellent first - quarter financial performance is a testament to our continued successful execution of our strategy focused on generating disciplined and profitable growth . We reported a strong 16.2 % non - GAAP operating ROE , non - GAAP operating income per diluted common share of $ 1.70 , and an impressive 89.3 % combined ratio . Our commercial lines NPW increased 28 % from a year ago , of which 16 points were due to the COVID - 19 - related $ 75 million return audit and mid - term endorsement premium accrual that reduced NPW in 2020. Commercial lines growth was driven by renewal pure price increases of 5.7 % and continued solid retention of 86 % . Each of our segments generated profitable results , with Investments a major contributor this quarter , ” said John Marchioni , President and CEO . " We are extremely proud of our successful track record in recent years of balancing growth with profitability , and consistently generating strong ROEs . Our results , in large part , have been driven by our superior distribution partner relationships , sophisticated underwriting tools and technologies , best - in - class customer experience capabilities , and culture of underwriting discipline . Our capital and liquidity position is the strongest at any time in our history . As we look to the remainder of 2021 , we are well positioned to build on that successful record , " continued Mr. Marchioni .