Explained: What are the Sensex and Nifty, and what does a weekly gain of 8% mean?

The Sensex tracks 30 large companies on the Bombay Stock Exchange, and the Nifty 50 tracks 50 on the National Stock Exchange.

Both rose more than 8% this week, according to reports.

The Sensex closed at 81,028.02 and the Nifty at 25,030.35 on Friday.

A weekly gain this large is rare, and reports say it was the best in about six years.

Markets can fall as quickly as they rise.

ETV Bharat says the Sensex gained 6,063.98 points, or 8.27%, over the six sessions of the winning run, and the Nifty gained 1,837.75 points, or 8%.

Business Standard’s closing headline called it a seventh straight day of gains, while ETV Bharat’s own figures describe a run of six sessions, so the count of the winning streak differs between outlets.

Other reports put the weekly gains at about 8.8% for the Sensex and 8.6% for the Nifty, which they describe as the best week in about six years, according to search summaries of Business Standard and CNBC-TV18 coverage.

Foreign institutional investors bought Rs 14,974.68 crore of equities on Thursday, according to exchange data cited by ETV Bharat.

Banks helped on Friday, and one summary says the Nifty Bank index rose 1,312 points to 59,086.

Broader markets were weaker than the benchmarks: ETV Bharat says the Nifty Midcap 100 fell 0.54% and the Nifty Smallcap 100 fell 0.87%.

In Asia, South Korea’s Kospi fell 6.02% and Japan’s Nikkei 225 fell 5.96%, and the Shanghai and Hang Seng indices each ended more than 1% lower, according to ETV Bharat.

Ponmudi R, chief executive of Enrich Money, told ETV Bharat that US markets were also under pressure, with the Dow down 3.4%, the S&P 500 down 4.36% and the Nasdaq down 5.52%.

The same comment attributed the US selling to a broad unwinding of AI-related trades, which is that analyst’s view and not an official finding.

Bombay Stock Exchange building, Mumbai (file image), Wikimedia Commons, CC BY 2.0