A study by Leung Weiwen from SMU, published in the peer-reviewed Journal of Benefit-Cost Analysis, showed that replacing Hong Kong's ageing buses with those meeting newer, more stringent emission standards could help save hundreds of lives. The findings also stated that at an estimated cost of HK$15 billion split evenly between the government and bus operators, the bus replacement would generate HK$26 billion in "net economic benefits" for Hong Kong by 2026, including lower hospital costs and regained productivity. Leung said that the proposals could be seen as the minimum subsidy needed to give private bus operators an incentive to replace all their pre-Euro IV buses.