Mumbai: The combined market capitalization (M-Cap) of seven of the country's top 10 companies diminished by Rs 27,131.73 crore in the past week, with IT bellwether Tata Consultancy Services emerging as the top loser.

The market worth of TCS declined by Rs 11,400.69 crore during the week taking its M-Cap to Rs 2,10,643.65 crore as on Fridays' trade on the BSE.

Similarly, another IT heavyweight Infosys Technologies also shed Rs 485.13 crore from its kitty taking its M-Cap to Rs 1,75,362.08 crore.

Two of the country's biggest lenders- SBI and ICICI Bank- together lost Rs 9,184.89 crore from their combined valuations. The M-Cap of SBI stood at Rs 1, 63,290.85 crore, while that of ICICI Bank was at Rs 1, 15,748.65 crore.

State-run power producer NTPC's market valuation also slipped by Rs 3,669.23 crore to Rs 1, 43,924.5 crore.

FMCG giant ITC also witnessed an erosion of Rs 910.75 crore from its kitty which stood at Rs 1, 32,335.15 crore.

Telecom player Bharti Airtel's M-Cap also eroded by Rs 1,481.04 crore to Rs 1,22,602.93 crore.

Meanwhile, corporate leader Reliance Industries, alongwith ONGC and Coal India were on the gainers side.

Energy major Reliance Industries saw its market worth advancing by Rs 3,224.27 crore to Rs 3,24,587.37 crore, while ONGC added Rs 10,865.46 crore to its valuation which stood at Rs 2,40,665.65 crore.

State-owned coal entity Coal India, too, saw its M-Cap swelling by Rs 3,158.18 crore to Rs 2,08,408.3 crore.

Meanwhile, during the week, the BSE benchmark Sensex lost 312.36 points or 1.68 per cent to settle at 18,174.09 in the previous session.