Shares in Ocado were down on the FTSE 250 in morning trading after the online grocery store reported a rise in sales of nearly a third in the year ended 28 November 2010.

Gross sales were reported as rising 29 per cent in the year to £551.1 million in the year long period. In the 16 weeks to 28 November gross sales were up 27.4 per cent to £178.9 million.

The average number of orders per week in the 16 weeks to 28 November increased 28 per cent to 99,741, while the average size of orders in the period was flat at £112.12.

Ocado said that in Christmas week gross sales increased 43.5 per cent to £12.3 million, whilst in the four weeks to 26 December gross sales rose 26.7 per cent to £50.9 million.

Tim Steiner, Chief Executive Officer of Ocado, said, "We are delighted to see the continued growth in demand for Ocado, a record number of customers shopped with us in this period. This would not have been possible without the heroic efforts of our staff rising to the challenge of delivering a record number of orders in sometimes challenging conditions. Our plan for dealing with extreme weather conditions enabled us to make over 98% of deliveries in the affected period."

By 10:55 shares in Ocado were down 1.72 per cent on the FTSE 250 to 182.80 pence per share.