Asda's low prices have dominated The Grocer 33 for the past six months but it's Morrisons not Tesco that is challenging it, however, to be Britain's cheapest retailer.
In the first half of 2007, Tesco came closest to stopping Asda's run as the cheapest retailer. However, in the past six months Morrisons has driven down its prices and leapfrogged Tesco to regularly occupy the second-cheapest position with an average basket total of £45.65.
Morrisons has been the only retailer to snatch the title of cheapest retailer from Asda during this period, aside from Tesco's single victory on 7 July.
For 20 of the past 27 weeks Asda has provided the cheapest prices with an average basket total of £44.51. It is now on its longest unbeaten run, notching up 11 consecutive weeks in the top spot.
Morrisons held the top spot for six weeks in total - four of which were consecutive wins in July and August - at the height of the supermarket price war.
Asda made £250m of price cuts this summer on 10,000 products but Tesco upped the ante, slashing the price of 3,000 products with a saving of £270m. Morrisons followed by reducing 2,000 products.
Tesco made great use of its swingometer adverts, launched in July. However, it spent 19 weeks in third position or lower in the rankings.
While retailers struggled to match Asda's prices, customer service and availability have improved across the board, with a more equally balanced share of Top Store awards than last year.
Waitrose is our current customer service champion with six Top Store awards to its name, impressing our mystery shoppers with its high level of staff responsiveness, store cleanliness, layout, service at the checkout, short queues and personal back-packing service.
Asda didn't win an award until 29 September but like its big four rivals, it ratched up five awards.
Somerfield has received only one award as it managed just three full baskets in 27 weeks.
Morrisons prides itself on keeping its shelves gap-free and has retained its title as top of the stocks with 97.86% - a 0.01 percentage point improvement on last year thanks to 12 full baskets and only 19 out-of-stocks. Asda finished in second place for availability with 97.4%. It had 23 out-of-stocks during the past six months and eight full baskets. However, the Leeds-based retailer's score dropped slightly from last year's 97.75%.
Waitrose's efforts to improve its availability score have paid off with a respectable 97.38%. It had 23 out-of-stock items - 10 fewer than Sainsbury's. Although Sainsbury's has provided 10 full baskets, it only scored 96.28% for availability. A spell of out-of-stock items during August brought its average down.
Tesco got its availability in better shape in the past six months, improving on the previous year's 96.87% score with 97.28% in 2007.
Somerfield has traditionally struggled with poor availability but has improved its score by one percentage point this year to 95.29%. However, 40 out-of-stocks during the past 27 weeks let the retailer down.
As for queue times, Somerfield only managed the second-quickest average time - five minutes and two seconds - despite having a lower number of products to process at the checkouts.
Shoppers at Waitrose spent the least time at the checkouts, just four minutes and 46 seconds - another indicator of its improved customer service. But Tesco deserves credit for slashing a minute off last year's time with a five minute and six second wait. And Asda may have finished the year the cheapest retailer, but it has the slowest checkout times at six minutes and four seconds.