They employ thousands of people and make millions of pounds – these are the largest firms in the city ranked by their income There are manufacturers, retailers, building firms and car dealerships, among others, and the list of Plymouth’s largest firms shows just how diverse the city’s economy is – and how much cash it is generating. The lineup comes from the Western Morning News’ Annual Business Guide, 2019, which contains a chart showing the 150 biggest businesses in Devon and Cornwall. The data for this year’s list has been compiled by Annual Business Guide partners PKF Francis Clark and supported by Gallagher, Natwest and Cornwall and Isles of Scilly Skills Hub. For the first time, the Top 150 has been ranked by turnover rather than employee numbers. We have also included companies that are based in the Plymouth travel-to-work area, so that includes South East Cornwall, and those that may be headquartered outside the city but have a Plymouth base or are active in the city. From tackling extreme weather and fatbergs to pioneering new technologies in water treatment and plastics recycling, it has been an eventful past year for Pennon Group (the FTSE 250-listed paren...