The latest figures from TNS WorldPanel, for the 12 weeks ending July 16, give Asda a 16.6% market share, marginally ahead of the 16.5% it achieved during the same period the previous year and an increase on figures released in May that gave it a 15.4% share.
During the period, shopper spending at Asda grew by 6%, ahead of total grocery growth of 4.6%.
This puts Asda in second spot ahead of Sainsbury's, which has a 16% share, but lagging behind undisputed market leader Tesco, which has a share of 31.5%. Tesco's share is up 1.4 points on previous figures released by AC Nielsen in May.
Chris Longbottom, TNS WorldPanel director, said: "Greater focus on competitive prices has helped Asda stage this resurgence", adding that the big names were also helped by the near disappearance of Kwik Save.
These latest figures also show that Morrisons stabilisation is continuing, with the brand recording a market share of 11.3%, a level it has held for the last year. Shopper spending at Morrisons was up 3% compared with the same period in 2005.
The research involves monitoring the spending habits of 20,000 UK households.
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