It was a close run thing, but Asda has wrested the availability award from Morrisons by the narrowest of margins.

There was little between the two retailers in our last survey but it was even tighter this year, with Morrisons' 97.68% rate of availability pipped by Asda's 97.79%.

Although Morrisons had 20 full baskets to Asda's 17, Morrisons had 38 out of stock items compared with Asda's 36.

Asda benefited to some extent from not stocking 21 items at the 50 stores we visited due to the store not running the line or space limitations, whereas Morrisons did not stock 12 items.

However, we can only assess the retailers on items they could potentially display on shelf so Asda's availability was deemed best.

Compared with last year, availability was worse across all the retailers except Asda, which has slightly improved on last year's 97.67%.

Tesco's and Sainsbury's availability has fallen since last year, with a whopping 57 out of stocks each.

Sainsbury's had seven fewer full baskets, while Tesco and Waitrose are credited for providing four more full baskets each.

Waitrose had the fastest checkout service, having cut its average time by 14 seconds to four minutes 40 seconds. Tesco was also faster, but Asda, Morrisons and Sainsbury's all had slower service at the checkouts this year.