Mumbai, Jan. 9: The Tata group is the first business house to see its gross market capitalisation top $100 billion at the start of 2011.

The group — with overall revenues of over $71 billion — has 28 entities listed on the bourses. In the past 12 months, its market capitalisation has leapt almost 40 per cent at a time the benchmark indices such as the sensex and the Nifty have risen about 17 per cent.

The Tata group saw its market capitalisation rise to $104 billion (Rs 4,70,107 crore) on January 5, surging past Mukesh Ambani’s Reliance group, which had a market capitalisation of roughly $78 billion (Rs 3,52,559 crore).

Last year around the same time, the Reliance group was ahead of the Tatas with its two listed entities.

Data collated by Accord Fintech show that on January 4 last year, the Reliance group had a market cap of $78 billion, while the Tata group stood at $75 billion.

This data show that Mukesh Ambani’s group has more or less stayed at the same level last year. However, Reliance Industries remains the numero uno with a market capitalisation of Rs 3,51,476.14 crore on January 5 — around the same as last year.

Adjustments have not been made on exchange rates for calculating the market cap in the two different years.

Market capitalisation represents the investor wealth that has been created by a corporation and is measured by multiplying the share price of a company with the number of outstanding shares of company.

Motilal Oswal, managing director of the eponymous firm Motilal Oswal Securities, said, “It has been a good year for the Tatas as acquisitions such as Corus and Jaguar Land Rover turned around. This development has contributed to the rise of the group’s market cap substantially.”

Within the Tata pack, Tata Consultancy contributes 48 per cent to the group’s market cap at Rs 2,26,655 crore as on January 5 this year, an increase of 54 per cent over last year’s level.

TCS was followed by Tata Motors at Rs 68,091 crore and Tata Steel at Rs 61,440 crore. However, Tata Motors had issued some more shares to holding company Tata Sons this year to compensate for part of the debt it had assumed during the JLR takeover. That is the reason why the Tata Motors stock jumped 55 per cent from Rs 827.40 to Rs 1,282.40 but the market capitalisation surged 71.5 per cent.

The Tata Motors stock climbed this year because of twin turbochargers — the terrific burst in automobile sales this year and the turnaround in JLR after two tumultuous years that followed the global economic downturn in early 2008.

Among the other large privately owned companies in the country, the Anil Ambani group has recorded a decline in market capitalisation at $25 billion (Rs 1,12,441 crore) compared with $30 billion (Rs 1,35,120 crore).

The market capitalisation of Reliance Communications is lower this year compared with last year. Reliance Capital has seen its market capitalisation shrink 26 per cent to Rs 16,157.73 crore.

However, Reliance Power has fared better with its market cap swelling to Rs 44,670 crore from Rs 37,414 crore last year.

Sunil Mittal-led Bharti group has also seen a rise in market capitalisation this year at Rs 1,32,875 crore against Rs 1,23,400 crore last year. Financial institution HDFC has seen an increase from Rs 1,54,179 crore in 2010 to Rs 2,10,718 crore this year.