Yields

■ Average wheat yields have increased almost four fold, from 2.3 tonnes per hectare in 1926 to just short of 10 tonnes per hectare in 2015, although yields have plateaued over recent years.

■ Over the past 90 years average wheat prices have fallen 84%; from £666 per tonne (in real terms) to just over £100 per tonne today.

■ The reduction in average crop incomes over the past 90 years has been more subdued at 36% due to the increasing crop yields.

■ With the exception of 2012 wheat has remained, in real terms, under £200 per tonne for the past 20 years.

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