 Residents of the city had an average age of 37 @.@ 1 years , younger than the 40 @.@ 2 average of the district and the 38 @.@ 6 average for England . Of the 17 @,@ 536 households , 35 % were one @-@ person households , 39 % were couples , 10 % were lone parents , and 15 % other . Of those aged 16 – 74 in the city , 27 % had a higher education qualification , higher than the 20 % national average . 
