£4 billion per year highest costs is costly report from Oxford Economics costs UK businesses £4.13bn each year headlines this week 28 weeks upwards of £30,000 highest costs time required to train an employee headlines this week headlines this week average cost of replacing a member of staff is £30,614 headlines this week highest costs highest costs highest costs Chartered Institute of Personnel and Development UK figures, highest costs headlines this week highest costs £4bn in 2014 28 weeks headlines this week highest costs highest costs headlines this week CIPD research headlines this week 28 weeks highest costs