Schools in the inner cities are revealed today as the big losers in a revamp of GCSE league tables.
Secondaries in Hull, the political backyard of Alan Johnson, the Secretaryof State for Education, will suffer most from the changes that place more emphasis on English and maths, The TES can disclose.
Gateshead, Knowsley and Newcastle upon Tyne will be the other serious casualties when the mechanism for calculating the tables alters in January.
By contrast, schools in the more prosperous Wokingham, Richmond upon Thames, Sutton and Torbay are the biggest gainers.
The new rankings are calculated not just on the proportion of pupils gaining at least five GCSEs at C or above, but will also include those also achieving English and maths.
The new tables show that in 17 areas, fewer than a third of pupils achieve the new criteria.
Latest statistics reveal that the proportion of pupils achieving the old measure rose from 56.3 to 58.1 per cent, the biggest gain for a decade.
However, the gender divide continues to be a problem as the figures show boys' achievements matched those that girls first managed seven years ago, with 63 per cent of girls gaining good GCSEs, compared to 53 per cent of boys.
In Hull, the proportion of pupils achieving the old benchmark, 51 per cent, will virtually halve to 26 per cent when the measure changes. In Gateshead it plummets from 70 to 45 per cent, which takes it from fifth out of 149 authorities to 64th. The figures in Knowsley slip from 48 to 26 per cent and in Newcastle from 55 to 33 per cent.
In Wokingham in comfortable Berkshire, the change will hardly be felt, the tightened criteria cutting the percentage of pupils achieving the central benchmark by only seven points, from 64 to 57 per cent. Here and in Richmond, Sutton and Torbay, most pupils with five passes have English and maths. This figure is less in Hull, Gateshead and Knowsley.
The changes will highlight the role of the controversial General National Vocational Qualifications. Critics say schools offering the courses, which count as four GCSEs in the tables under both measures, have been able to boost their results artificially.
Under the new measure, GNVQs are less of a factor, it is said, because pupils need to pass both English and maths, in addition to a GNVQ, to count towards league table success. Previously, a single GCSE pass in any subject with a GNVQ was enough.
The effect on Hull will be particularly embarrassing for Mr Johnson. The city hauled itself off the bottom of the rankings under the old measure, its results soaring from 29 to 51 per cent since 2002.
Under the new benchmark, progress is much less spectacular, statistics having improved by only five points from 2002, from 21 to 26 per cent. This leaves Hull back at joint bottom, with Knowsley.
City technology colleges and academies will also lose their positions when the measure changes, the Government's statistics reveal. Average results at city technology colleges drop 24 points, from 89 to 64 per cent, when the measure is changed. In academies, they fall from 49 to 31 per cent.
Community schools drop only 14 points, from 54 to 40 per cent.
Old measure, Top five local authorities:
1 Redbridge (72%)
2 Sutton (71%)
3 Trafford (70%)
4 Gateshead (70%) 5 Buckinghamshire (69%)
New measure, Top five local authorities:
1 Sutton (63% )
2 Buckinghamshire (59%)
3 Redbridge (59%)
4 Kingston upon Thames (58 %)
5 Wokingham (57%)
Old measure, Bottom five local authorities:
144: Leicester city: (46%)
145: Islington: (46%)
146: Nottingham city: (44%)
147: Bristol: (44%)
148: Greenwich: (41%)
Bottom five local authorities:
144: Portsmouth: (29% )
145: Manchester: (29%)
146: Nottingham city: (28%)
147: Hull (26%)
148: Knowsley (26%)
Old measure shows percentage of pupils achieving five or more GCSEs or vocational equivalent at A*-C
New measure shows percentage of pupils achieving five or more GCSEs or vocational equivalent at A*-C, including English and maths
All rankings are based on pupils' performance in 2006.