Among the countries that practice grade repetition and that have relevant data available, in Estonia, Iceland, Ireland and Israel, the direct and opportunity costs of using grade repetition for one age group can be as low as 0.5% or less of the annual national expenditure on primary- and secondary-school education - or between USD 9 300 and USD 35 100 per repeater (Figure 4.2 and OECD, 2013a, Table IV.1.6). In Belgium and the Netherlands, the cost is equivalent to 10% or more of the annual national expenditure on primary and secondary education - or as high as USD 48 900 or more per repeater. These estimates are based on the assumption that students who repeat grades attain lower secondary education, at most. As individual schools receive their funding in relation to the number of students enrolled, they do not have to absorb those increased costs or bear the opportunity costs of lost output (Field, Kuczera and Pont, 2007). By contrast, practices that can reduce the use of grade repetition, such as personalised and intensive intervention, very often have direct costs for schools.