Unions are calling for an overhaul of the minimum wage system after reports suggest thousands of workers are left ‘out of pocket’. More than 700,000 workers aged 18 to 20 face a “penalty” of thousands of pounds a year due to being paid a lower rate of the minimum wage, official data from The Trades Union Congress (TUC) shows. The National Minimum Wage is the minimum pay per hour almost all workers are entitled to. People classed as ‘workers’ must be at least school leaving age to get the National Minimum Wage. They must be 23 or over to get the National Living Wage, although this threshold wil…