Tesco put the pedal to the metal in September - ramping up the number of featured space promotions it ran by more than 10% compared with the previous month.

It offered shoppers 2,402 deals in the four weeks ending 29 September - just 50 deals behind regular top promoter Sainsbury’s.

Much of Tesco’s activity was focused on ‘power aisle’ promotional space, which accounted for almost 80% of its offers - up from 65% of its promotions this time last year.

It has shifted away from using the back aisle, where shoppers would have found less than 9% of its offers compared with about 20% last year.

The retailer has also upped the proportion of promotional space given over to alcohol from 15% last year to 20%, while reducing the promotions offered on impulse lines from about 23% of its total deals to 18%.

Another change has been the mix of promotional mechanics used. Tesco has reduced its use of bogofs - which accounted for one in every 10 of its offers last year and now make up less than 4% - in favour of straight ‘money off’ deals.

The shift away from bogofs contributed to the average saving at Tesco falling from 33% last September to 32.3% this year. However, month on month, it was one of only two retailers (the other being Waitrose) that offered deeper average savings.

Sainsbury’s reined in month-on-month average savings the most - from 34.9% in August to 33.4% this month.

It did, however, post the biggest year-on-year increase in the number of promotions it ran - up from 2,294 in September 2012 to 2,452. Like Tesco, it is making greater use of the power aisle, running 70% of its offers there compared with 66% last year as it reduced the proportion of its deals in the till aisle.

Asda, too, has reduced the share of deals in the till aisle to run more power aisle offers. Year on year, Asda has made greater use of x-for-y offers and less use of half-price deals, contributing to the typical saving falling from 29.5% a year ago to 28.9%.

Morrisons has also been favouring x-for-y over half-price, bringing the steepest year-on-year decline in average saving, from 38.2% a year ago to 34.9% last month.