Wingstop Inc. /zigman2/quotes/206814832/composite WING -0.65% shares rose 3.3% in Tuesday premarket trading after the chicken wing chain announced preliminary first-quarter results that show a sales rise despite shifting to takeout-only amid the coronavirus pandemic. Wingstop Chief Executive Charlie Morrison said in an open letter that takeout and delivery represented about 80% of the company's sales before the pandemic, and digital sales represented 40%. The company is running a free delivery promotion through April 30. For the first-quarter, same-store sales rose 9.9%, with same-store sales rising 11.5% in the period between Dec. 29, 2019 and Jan. 25, 2020 and declining thereafter. "[W]hile we have seen a slight decline in overall transactions due to the loss of dine in, growth in our average ticket has surpassed these transaction declines as we're primarily serving meals for families," Morrison said. Company-owned same-store sales rose 6.2% for the period. Sales rose 18.6% to about $429.9 million. And digital sales were up 47%. The company is extending its incentive program for full-time workers, which will offer up to $150 bonus pay per week through April 30. Wingstop shares have jumped 14.2% over the past year while the S&P 500 index /zigman2/quotes/210599714/realtime SPX -1.12% is down 8% for the last 12 months.