The proposed bond's Ba2 senior secured rating reflects the airport's strong market position and robust passenger traffic, which would likely grow at a high single-digit percentage per annum over the next 18 months under Moody's base case scenario, it said. The rating agency however, said Delhi Airport's ratings are constrained by its planned capacity expansion, which would exert downward pressure on its financial metrics, the evolving regulatory environment in India and its obligation to pay 45.99 per cent of its revenue to the Airports Authority of India as a concession fee. After accounting for the proposed USD notes, Moody's expects that DIAL's funds from operations/debt would remain weak over the next 2-3 years, with a very limited buffer above the minimum tolerance level of 3-4 per cent Moody's said.