For the first time, primary schools are becoming academies at a faster rate than secondary schools.

But ministers are unlikely to celebrate this as evidence of growing popularity of their flagship policy among primaries, as the conversion rate in both phases slowed over the last year.

That is one of the main findings of a report by the National Foundation for Educational Research, published today.

The study, ‘A tale of eight regions’, examines how school structures have changed in the different areas covered by regional schools commissioners (RSCs) - the powerful civil servants who oversee academies, and, increasingly, non-academies, in their patch.

Here are six key findings:

1. Academy growth in the primary sector now exceeds the secondary sector
   This year was the first time this has happened since the coalition government put “rocket boosters” under the academy programme in 2010. However, it is not because the rate of academisation among primary schools is increasing - it just declined slower than that of secondary schools.
   Growth in the secondary sector was 8.4 per cent in 2013 but now stands at 2.9 per cent in 2016. This compares to the primary sector, where growth has fallen from 4.4 per cent in 2013 to 3.7 per cent now.
2. There are stark differences in the proportion of academies in different regions…
   But the academics say this does not seem to be linked to the number of underperforming schools, or their characteristics.
   “A number of factors may be driving this variation”, they write, “including a lack of suitable sponsors to take on underperforming schools, or different RSC approaches to tackling underperformance”.
   The south-west, where 38 per cent of schools have converted, is the most academised region. It was highest both for primaries (32 per cent) and secondaries (76 per cent).
   The North of England, and Lancashire and West Yorkshire, were the least academised, each with 18 per cent of schools having converted.
3. …and the gap between the regions is growing
   The gap between the regions with the highest and lowest proportions of academies has increased over the past 12 months - from 16 percentage points to 20 percentage points.
4. The differences in academisation within regions is “even more striking”
   The South-East London and South London region - a single area under one RSC - has the biggest gap between two authorities within its borders: 87 per cent of schools in Bromley are academies but in neighbouring Lewisham the figure is just six per cent.
   The variation is at its lowest in the West Midlands RSC region - but there is still a 35 percentage point gap between the proportion of schools that are academies in the authorities of Cheshire West and Chester, and Stoke on Trent.
5. The conversion rate for primaries is highest where there are already lots of secondary academies
   The authors highlight this trend in the South-West England region, and the East of England.
   In the South West, 76 per cent of secondaries are academies, and there was a 7.2 percentage point increase in primary academies since September 2015.
   In the East of England region, 73 per cent of secondary schools are academies, and there was a 5.6 percentage point increase in primary academies in the same period.
   The north of England, and Lancashire and West Yorkshire, which have the lowest proportions of secondary academies, saw a below average growth in the primary phase.
6. Underperforming schools are most likely to be turned into academies if they are in the East
   The researchers found that 83 per cent of secondary schools in the East of England that fell below the government’s minimum floor standard in 2013 had become sponsored academies by September 2016.
   The same region had the highest figure for the primary phase, too, at 42 per cent.
   Primaries below the floor in the North, and secondaries in the North and the West Midlands, were much less likely to become sponsored academies.
   The paper says there were no clear patterns to explain these variations, but the authors speculate that a lack sponsors with the capacity to take on more underperforming schools could be one reason.

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