Discounters continue to dominate The Grocer's Top 50 ranking of independent grocery retailers, as supermarkets struggle in the tough economic climate.

Of the eight discounters in this year's list, pre-tax profits rose by an average of 47%, with sales up 19%, leaving them with an enviable profit margin of 4.1%. Rapid store expansion boosted figures, with three discounters B&M Retail, TJ Morris and Heron Foods notching up double-digit growth in store numbers.

In contrast, the nine independent supermarkets that made the grade saw profits fall 35% last year. Sales were up a paltry 1%, in stark contrast to last year, when sales rose 5% and profits were up 25%.

Top of the pile for the second year running was Wilkinson, which posted a 7% sales hike to £1.56bn and a 120% increase in profits. The company plans to grow from 337 stores to 500 by 2014 and is looking for stores of a minimum 10,000 sq ft in the South East and South West of England, and Scotland.

Total sales for the Top 50 were up 10% on last year to £7.7bn with profits up 35%, resulting in a profit margin of 3%. However, taking out the discounters, sales were up just 4%, and profits by 20%, halving profit margin to just 1.5%.