New investors registered on the National Stock Exchange crossed the nine-crore mark as the stock markets scaled newer records amid surging demand from retail investors.The total number of client codes registered with the exchange stands at 16.9 crore, the NSE said in a statement on Friday. The unique investor count rose from eight crore to nine crore in only five months, while it took about nine months to increase from six crore to seven crore, the statement said."The investor base has seen more than a three-fold jump in the last five years, facilitated by rapid growth in digitization, rising investor awareness, financial inclusion, and strong market performance."In a December statement, NSE noted that the country's market capitalisation crossed $4 trillion and is now ranked fourth in the world, behind only the U.S., China and Japan.The benchmark Nifty 50 surpassed the milestones of 20,000 on Sept. 11 and 21,000 on Dec. 8, 2023. It went past the 22,000 mark on Jan.15, and closed at a record high of 22338.75 on March 1, 2024.Since October 2023, people in Uttar Pradesh and Maharashtra have contributed the largest number of new investors, together accounting for more than a quarter of all new additions.However, the highest number of unique registered investors are from Maharashtra, with 1.6 crore investors, followed by Uttar Pradesh and Gujarat.Over 46% of all new investor registrations in the last five months originated from districts beyond the top 100 districts, the NSE said. With almost 1.6 crore new SIP accounts opened between October 2023 and January 2024, indirect participation has also increased meaningfully, NSE said.From the beginning of FY24 up to Feb. 29, 2024, the Nifty 50 returned about 27%, while the Nifty 500 delivered a 38% return over the same period, according to the NSE.