§ Take-up tends to be higher as the amount of entitlement increases. The estimated proportion of benefit taken up in 1981–85 per cent.—was higher than the proportion of those entitled at any one time who actually claimed—71 per cent. With the exception of the sick and disabled group the average amount of unclaimed benefit increased between 1979 and 1981 at a faster rate than the rise in supplementary benefit scale rates. There were two reasons for this. First, housing costs increased ever the period at a faster rate than the scale rates. Secondly, there were changes in the family composition of the non-claimants; there were proportionately more married couples, who tend to be entitled to more benefit than single persons, in 1981. The reduction in the average amount of unclaimed benefit by the sick and disabled is also due to change in family composition; in 1981 a higher proportion of non-claimants were single people than in 1979.