It has also been suggested that the incorporation of GCSE awards into school league tables, and the setting of School level targets, at above national average levels of attainment, may be a driver of GCSE grade inflation. At the time of introduction the E grade was intended to equivalent to the CSE grade 4, and so obtainable by a candidate of average/median ability; Sir Keith Joseph set Schools a target to have 90% of their pupil obtain a minimum of a grade F (which was the 'average' grade achieved in 1988), the target was achieved nationally in summer of 2005. David Blunkett went further and set schools the goal of ensuring 50% of 16-year-olds gained 5 GCSEs or equivalent at grade C and above, requiring schools to devise a mean for 50% of their pupils to achieve the grades previously only obtained by the top 30%, this was achieved by the summer of 2004 with the help of equivalent and largely vocational qualifications. Labelling Schools failing if they are unable to achieve at least 5 Cs, including English and Maths at GCSE, for 40% of their pupils has also been criticised, as it essentially requires 40% of each intake to achieve the grades only obtained by the top 20% at the time of the qualifications introduction.