Economy Delhi air quality likely to deteriorate over next 2 days Updated : December 18, 2018 08:29 PM IST However, the agency said the pollutants will over the next two days reach the upper level of the "very poor" zone and then gradually decline. The overall Air Quality Index (AQI) of Delhi at 4 p.m stood at 353 (very poor). Subscribe to Moneycontrol PRO at just Rs.33/- per month for the first year. Use code SUPERPRO. Limited period offer. Available on Web and Android.