LONDON (Reuters) – Marks & Spencer (OTC:) has maintained its position as Britain’s fastest growing food retailer, market researcher NielsenIQ said on Tuesday, indicating its turnaround plan is gaining momentum.

It said M&S’s sales rose 12.3% in the 12 weeks to Jan. 29 year-on-year, giving it a UK grocery market share of 3.6%, up 0.4 percentage points on the year.

Last month, M&S nudged up its profit outlook after it reported a strong Christmas, and hopes are rising its latest attempt at a turnaround could succeed after decades of false dawns.

NielsenIQ data revealed that Tesco (OTC) the market leader was Britain’s best-performing of Britain’s Big Four Grocers.

The 0.3% decline in sales was significantly higher than the falls at Sainsbury’s and Morrisons (which had drops of 3.7%, 4.3%, and 6.9%, respectively).

This data was similar to Kantar’s market research figures last week. However, Kantar does not include M&S in its monthly reports.

M&S also had weaker comparative sales numbers than the big four in the same period of 2020-21.

NielsenIQ reported that overall UK supermarket sales declined 2.9% in the four weeks ending Jan. 29, according to NielsenIQ.

Comparatives are very difficult, since the United Kingdom was locked down by COVID-19 last year and its sales rose 10.6%.