With the January transfer window well underway and rumours flying, we’ve analysed every winter Premier League signing since it was created in 2003 to reveal what type of player tends to make an immediate impact and which are likely to be remembered as flops. The age, nationality and position of a player are all considered, along with the league in which they currently ply their trade. There’s good news in particular for Manchester United’s likely targets, who would be following in the footsteps of previously successful imports should they move to Old Trafford.