Agriculture Why the monsoon is so crucial for India Updated : April 17, 2018 06:42 AM IST India's monsoon rains are likely to be 97% of their long-term average in 2018. A normal, or average, monsoon means rainfall between 96% and 104% of a 50-year average of 89 cm (35 inches) in total during the four-month monsoon season from June. 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.