Coles Group’s full-year result landed with a thud on Tuesday, with shares in the retailer down 5.8 per cent as investors digested a shock blowout in costs in the six months ended June 30.

The 9.7 per cent increase in the cost of doing business inside Coles’ flagship supermarket division was driven in part by rising wages following the minimum award decision and a jump in employee leave entitlements, a function of rising wages and higher bond rates, which are used to discount leave provisions.