Hull and East Yorks family firms in Top Track 250

It's interesting to see five Hull and East Yorkshire companies in the Sunday Times Top Track 250 of private firms. The list ranks privately-owned companies by sales.
The local firms listed are: Rix (no. 59); Andrew Marr International (68); Arco (152); Swift Group (197); and William Jackson Food Group 238).
The recurring theme is long-standing, stable family ownership. Rix is the oldest with roots in the early 19th century and its current business dating from 1927. William Jackson was founded 1851; Arco 1884; Marr 1902. Swift is the baby, started in 1965. It's a story of success and longevity by companies steered by generations of family members.http://www.fasttrack.co.uk/fasttrack/leagues/top250leaguetable.asp?siteID=5&searchName=&yr=2011&sort=num&area1=99