I'm beginning to wonder if its symptomatic of age, you start with No trousers as a toddler, as a child you are forever pulling them up because lets face it average sizes for childrens waists have gone stupidly large, both my kids fit in the lower age groups waist size. then in your teens you wear them really low, about the knee's they creep up in your twenties to below your waist. by thirty they're on your waist. by forty they're starting to climb and do so each decade until at 70 they're under your armpits.