The BSE Sensex, launched on January 1, 1986, will mark its 40th anniversary in January 2026. Its market capitalization has grown from ₹12 lakh crore in 2005 to ₹169 lakh crore currently. Over four decades, the Sensex has delivered positive returns in most years, with the Total Return Index showing positive returns in 79 out of 40 years. Financial services and IT sectors have seen significant shifts in their weightage within the index.