Focusing on its 'F-plan' - food, families, females and forty/fifty-somethings - helped tenanted pub group and brewer Marston's post flat turnover in the six months to October 3 in spite of poor summer weather and fragile consumer confidence.Like-for-like sales fell by 0.6% over the whole year, but like-for-like food sales climbed by 2.8%. In the nine weeks to October 3 overall like-for-like sales were up by 5.7%, with drinks sales posting a 1% rise.Marston's said its pub division saw a 7% fall in like-for-like profits, while the Marston's Beer Company, whose range includes Marston's Pedigree, increased market share.The firm, which launched a rights issue in July to take advantage of the depressed property market to acquire new sites, said net debt of £1.1bn on October 3 was £169m below last year's level.Marston's said it remains cautious on the UK economy, while noting that it is benefiting from cost inflation pressures easing.