LONDON (Reuters] – In four weeks from May 21, Britons visited more supermarket stores than ever before as they sought out the lowest prices and a better quality of life. This was according to NielsenIQ, a market research company.

British households have been facing an increase in their disposable income. Inflation reached a record high of 9% in April, which is a new 40-year high. It will likely rise even further.

The government has announced last week a package worth 15 billion pounds ($19billion) to help households that are having trouble meeting their rising energy bills.

“Shoppers are becoming more considered in what they buy and the current challenge for supermarkets is to improve volume growth by getting more items into the shopping basket,” Mike Watkins, NielsenIQ’s UK head of retailer and business insight, said.

Supermarkets have the upside of allowing shoppers to dine at home more often as their finances are squeezed.

NielsenIQ stated that the total UK grocery store sales increased 0.6% in four-weeks, driven by an increase of 2.3% in the week ending September 30.

According to the report, promotional spending fell from 21.5% to 20.4% of total value sales in the last month. This suggests that retailers are not keen to promote volume when customers want to shop less.

Market researcher says the coming Platinum Jubilee bank holiday weekend could provide a welcomed, but short-term boost in grocery sales.

According to the survey, 20% of households expect to purchase extra groceries on weekends.

NielsenIQ said over the 12 weeks to May 21, total sales fell 1.7% year-on-year, with market leader Tesco (OTC:), Marks & Spencer (OTC:), German-owned discounters Aldi and Lidl and the Co-operative all gaining market share.