The term Sensex refers to the benchmark index of the BSE in India. The Sensex is comprised of 30 of the largest and most actively traded stocks on the BSE and provides a gauge of India's economy. It is float-adjusted and market capitalization-weighted. The Sensex is reviewed semiannually each year in June and December. Created in 1986, the Sensex is the oldest stock index in India and is operated by Standard & Poor's (S&P). Analysts and investors use it to observe the cycles of India's economy and the development and decline of particular industries.