Shares of Interglobe Aviation which runs the IndiGo airline tumbled 12% on Thursday after the company\u2019s Q4 results missed analyst estimates on rising fuel expenses. Interglobe Aviation shares were trading at Rs 1,158.6, down by more than 13%. Notably, India\u2019s largest airline by market share has reported a 73 percent drop in net profit to Rs 117.6 crore as compared with the same quarter last year. This compares with Rs 478 crore consensus estimate of analysts tracked by Bloomberg. \u00a0Surging fuel costs as indicated by a 33.5 percent surge in aircraft fuel expenses on a year have weighed on the profits of the budget carrier. Apart from that, the airline has also reported a foreign exchange loss of Rs 92.5 crore as against a gain of Rs 160 crore in the same quarter last year. The revenue from operations came in at Rs 5,799.1 crore as compared to Rs 4,848.2 crore in the same period previous fiscal. The results also assume heightened significance even as Aditya Ghosh, the president of IndiGo has decided to step down from the firm. Taking stock of IndiGo\u2019s Q4 results, IDFC has downgraded the shares to neutral with a target price of Rs 1,293. IDFC said that the yields have been weak. The research firm expects the yields to improve in Q1 FY\u201919. IDFC has lowered FY19\/20 estimated earnings by 19.5% respectively. Meanwhile, market regulator SEBI is examining the cause for the worst share price drop in InterGlobe Aviation stock in seven months before the company announced the resignation of its president, Bloomberg reported citing sources. The Securities and Exchange Board of India (SEBI) is investigating a 6.1 percent drop in the company\u2019s shares on April 27 as well as the reasons behind the delay in the disclosure of Aditya Ghosh\u2019s exit by the company, sources told the news agency.