What a difference a year makes.

This time last year, Sainsbury’s reported bumper fourth-quarter results – chalking up like-for-like growth of 3.6%, excluding fuel, and total sales growth of 6.3% in the 10 weeks to 16 March 2013.

Yesterday, it revealed like-for-like sales were down 3.1% and total sales fell by 1%, both excluding fuel, in the 10 weeks to 15 March 2014, bringing its run of 36 consecutive quarters of like-for-like growth to an end.

The negative numbers, however, are not as bad as they appear at first glance.

Sainsbury’s figures were boosted by a number of factors in 2013, leaving it with very tough comparatives.

Last year, it cited a “particularly strong” Mother’s Day, and a “very successful” Red Nose Day for its bumper performance. It also benefitted from being unaffected by the horsemeat scandal, and from cold, dry weather.

Fast forward to 2014 and Mother’s Day hasn’t happened yet, Red Nose Day doesn’t take place this year (although its spin-off Sport Relief is this weekend) and as CEO Justin King pointed out this morning, the weather over the quarter has been “warm and wet”.

Add to this King’s claim that the market is “now growing at its slowest rate since 2005”, and it’s no surprise sales were down.

As a further silver lining, last week’s Kantar Worldpanel data showed that Sainsbury’s continues to grow. It was the only member of the big four to hold its market share year-on-year at 17% and match overall market growth of 2.2%.

In contrast, Tesco, Asda and Morrisons all recorded market share declines. Tesco and Morrisons also saw a drop in actual sales.

One quarter of negative numbers doesn’t mean the beginning of the end, but commentators will be watching Sainsbury’s closely to see whether today’s results become a long-term trend – especially if the supermarket price battle sparked in recent weeks by Tesco, and more recently Morrisons, escalates into a full-scale war.