New Delhi, December 17 (PTI): The combined market valuation of 6 of the 10 most valued firms surged by Rs 31,645.83 cr last week, with HDFC Bank emerging as the biggest gainer. Others on the gainers’ list were ITC, Maruti Suzuki, HDFC, Infosys and ONGC. However, Reliance Industries (RIL), TCS, HUL and SBI suffered losses in their market capitalisation (m-cap) for the week ended Friday. The valuation of HDFC Bank surged Rs 8,566.49 cr to Rs 4,84,757.35 cr. HDFC’s m-cap jumped Rs 7,338.91 cr to Rs 2,75,147.96 cr and that of Infosys climbed Rs 5,030.42 cr to Rs 2,35,085.78 cr. The valuation of Maruti Suzuki rose by Rs 3,720.12 cr to Rs 2,76,826.17 cr and that of ITC advanced Rs 3,717.41 crore to Rs 3,22,682.82 cr. ONGC’s mcap went up by Rs 3,272.48 cr to Rs 2,34,655.71 cr. In contrast, the valuation of Tata Consultancy Services (TCS) skidded by Rs 10,174.44 cr to Rs 4,87,731.76 cr. RIL suffered an erosion of Rs 624.67 cr in market valuation to Rs 5,82,618.99 cr and that of SBI fell by Rs 345.28 cr to Rs 2,69,967.48 cr. The m-cap of Hindustan Unilever Ltd (HUL) declined by Rs 335.49 cr to Rs 2,86,825.88 cr. In the ranking of top-10 firms, RIL stood at number one position, followed by TCS, HDFC Bank, ITC, HUL, Maruti, HDFC, State Bank of India (SBI), Infosys and ONGC. Over the last week, the Sensex notched up a significant gain of 212.67 points, or 0.63%. The broader Nifty was up 67.60 points, or 0.65%.