MUMBAI: Since August 23, Dalal Street investors were used to getting some announcement by finance minister Nirmala Sitharaman every Friday evening aimed at boosting a slowing economy. Throughout this week too there were messages and posts on various social media platforms, speculating about what the finance minister would do on the evening of Friday the 20th. This time, Sitharaman surprised D Street investors by announcing some radical changes to taxation rules in the morning itself.Following the announcement, as investors, traders and speculators rushed to buy, the sensex rallied 1,921 points — its second biggest single-day gain ever — to close at 38,014 points. In the process, investors grew richer by Rs 7.1 lakh crore, the biggest-ever daily gain, with BSE’s market capitalisation now near Rs 145 lakh crore. In other words, the market cap has crossed the $2-trillion mark again.Firstly, according to market veterans, the cut in tax rates for corporates has the potential to boost net profit for leading corporates by about 6-7% on an average. Some rule changes could also attract foreign capital. And these in turn could lead to more people getting employed.“The move will structurally enhance corporate profitability, encourage Indian businesses to become globally competitive and also attract FDI to set up manufacturing base in India to capitalise on the opportunities opening up due to the shift in the global trade scenario,” said Hemendra Kothari, chairman, DSP Investment Managers.Reports by broking houses pointed out that if a majority of the NSE’s top 500 companies move to the new tax structure, that will boost their net profit. Most broking houses said that the government’s decision will make India shares attractive for foreign funds as well as domestic players.A report by Yes Securities noted that the estimated combined net profit of NSE 500 for the current fiscal will rise by about 12%, up from 5% earlier. Another report by CLSA, a leading foreign brokerage, noted that corporates could see an average gain of 6-7% in their earnings per share (EPS) from the FM’s tax cut decision.A report by Credit Suisse pointed out that consumer companies would be the biggest beneficiaries of FM’s decisions with Avenue Supermart (D-Mart), Page Industries and Britannia leading the pack with EPS gains of between 15% and 18%.Another report by K R Choksey Securities said that banks will also gain, with HDFC Bank, ICICI Bank and IndusInd Bank leading. On the other hand, software exporters, which mostly operate out of special economic zones that enjoy special tax incentives, will gain only marginally.Friday’s trading pattern rewarded the gainers while the others lagged behind. Among the sensex stocks, HDFC Bank, up 9.1%, was the biggest contributor to the index’s gain, followed by Reliance Industries and ICICI Bank. Among the sensex laggards were Infosys and TCS, BSE data showed.The day’s session also recorded one of the largest trading volumes by foreign funds with a total at about Rs 34,000 crore. The net inflows by foreign portfolio investors (FPIs), was, however, limited to just Rs 35 crore. In comparison, domestic funds recorded a net buying figure of over Rs 3,000 crore, one of the biggest in recent months.