To ask the Scottish Executive what percentage of pensioner households had incomes (a) before housing costs and (b) after housing costs of less than (i) 70%, (ii) 80%, (iii) 90% and (iv) 100% of the relevant year's Great Britain mean income in (i) 1979-81, (ii) 1988-89, (iii) 1992-93, (iv) 1996-97, (v) 1997-98 and (vi) 1998-99.