Booker has now converted 100 of its 173 depots to its Booker Extra format.

The wholesaler has been converting its depots to the format, which offers customers a better range, since 2006.

Booker's Reading depot was the 100th to receive the revamp and was unveiled this week. The depot is lighter and brighter with an improved layout, signage and ranges.

Booker claims the cost of converting the branches is recouped in about a year thanks to increased sales.

Booker this week reported a 4.9% increase in total sales for the 12 weeks to 18 June. Non-tobacco sales were 4.5% higher, while tobacco sales rose by 5.5%.

On a like-for-like basis, total sales rose 4.8%, non-tobacco sales 4.3% and tobacco sales 5.5%. Fresh departments performed particularly well with fruit and vegetables up 60% and meat up 11%.

"The business is performing in line with expectations and the outlook for the year as a whole remains unchanged," said CEO Charles Wilson.

"Booker has continued to make progress in the first quarter against a strong comparative period last year.

"We are helping 431,000 independent businesses compete by improving choice, having competitive prices and further enhancing service."