Shares of Gap were gaining after the market closed following better-than-expected May same store sales of 1%, helped by positive comparable sales in its Banana Republic and Old Navy brands. Forecasts were calling for Gap to report same store sales to rise just 0.2%. Gap’s overall net sales rose 4% compared to a year earlier to $1.27 billion. Still, same store sales for Gap flagship brand declined 3% last month. Banana Republic showed positive 3% growth while Old Navy experienced same store growth of 2%. After a rough first quarter, retailer's same store sales in May continued to improve following the April jumpstart, that was likely pegged to an improvement in weather.