A study from CIES Football Observatory says the 23-year-old Jonjo Shelvey was the best-value buy of the January transfer window.
They claim the England international is actually worth £23.5m, which is £11.5 more than Newcastle United spent on the midfielder. However, Chinese club Guangzhou Evergrande overspent by £18.43m on Atletico Madrid's Jackson Martinez and Bounrmouth also overpaid in their £7m re-purchase of Lewis Grabban from Norwich.
Source: transfermarketweb.com