Food sales decline as milk soars in price by up to 16%: Kantar

But discount grocer Lidl has reported the slowest rate of sales decline of the main four supermarkets.

Analysis by data company Kantar found that spending in supermarkets and convenience stores fell by 3.6% in the year to September 4 as grocery price inflation hit a new high of 6.3%.

That meant the average item was up in price by 4.7% — but the scale of increase was even greater for essentials like milk and pasta, up by 16.1% and 14.4% respectively.

But senior analyst Emer Healy said the back to school rush did mean purse-strings had to be loosened, even if prices were higher.

Over the last three months, grocery sales are up 3.5% with customers making an average of 53 trips to stores over the period

As the new term was about to begin, they spent an additional £592,000 on chilled drinks, £2.5m on biscuits and £2.9m more on frozen food.

Tesco, which has around 50 stores here, remained Northern Ireland’s number one grocer, with a chunky 35.7% share of the market. And new shoppers were also flocking to its shops around Northern Ireland, adding an additional £42.7m in sales.

Sainsbury’s, Asda and Lidl complete the top four, Ms Healy said.

“Sainsbury’s holds 17.1% share with Asda just slightly behind at 16.3%, as they each saw over 10,000 more shoppers in store.

“All retailers declined compared to last year, with Lidl seeing the slowest decline at 0.7%, bringing its share of market to 7.0%. Amongst all retailers, Lidl had the biggest boost of new shoppers at 9%, spending an additional £20.9m.”