All of the big four supermarket groups faced declining sales over the past 12 weeks - in contrast to Aldi and Lidl which achieved record-breaking growth, according to Kanter Worldpanel.
Aldi experienced its highest ever growth of 35.5%, taking its market share to a record 4.6%, while Lidl now accounts for 3.4% of the market.
The big four sales decline was accentuated by the late falling of Easter this year, said Edward Garner, director at Kantar Worldpanel.
“Nevertheless, they have also seen worrying share declines, with the most resilient performance coming from Asda this period,” he added.
The grocery market grew by only 0.6% over the 12-week period until 30 March, which was distorted by the late falling of Easter. Kantar estimate that Easter accounts for market growth of 0.9%, meaning that ‘corrected’ market growth would stand at 1.5% - still low by historical standards.
Waitrose continues to hold to its record 5.0% market share, while The Co-operative Food held to its current 6.1% share over the past four quarters.
Frozen food outlet Farmfoods reached a record share of 0.8% over the 12-week period.