Earnings upgrades, market share gains, and strong passenger growth helped InterGlobe Aviation gain 26 per cent over the last month, making it the second-biggest gainer among BSE200 companies. Nearly seven per cent of those gains came on Thursday due to another month of robust passenger growth. The company, which runs an airline under the IndiGo brand, posted a 19.4 per cent year-on-year jump in passenger volumes for March as compared to industry growth of 18 per cent. Its market share has improved 150 basis points over the previous month and by 270 basis points over March 2016 quarter, to 39.9