Airtel has gained nearly ₹39,300 crore in market cap in the past three trading sessions, while Vodafone Idea added over ₹8,800 crore to its market value. Shares of Vodafone Idea have surged 104% since Thursday's close whereas Airtel saw its shares rise 21% since then. The telecom operators on Monday announced tariff hikes that will take effect next month.