Desi MO (McClellans Oscillator for NSE) – 21st DEC 2020 December 21, 2020December 21, 2020 R M Blog MO at -42 Declining volumes exceed 90% McClellan’s Oscillator – Calculation and Interpretation Indiavix Declining Volumes NSE – McClellan Summation index (MSI) MSI is a summation of MO, hence its absolute value depends upon the beginning date of summation.