Nitrogen use efficiency in Scotland: annual report 2025

Nitrogen Use Efficiency

In 2022, the whole economy Nitrogen Use Efficiency (NUE) figure was 27%. Although the whole economy figure is dominated by food production, this figure is lower than the NUE for food production due to the inclusion of sources such as transport which produce no useful nitrogen outputs. The NUE for all food production is 33%, with the figure for agriculture (33%) being very similar, given that agriculture dominates food production. The 33% figure for all of agriculture comprises the value for arable agriculture of 70% and that for livestock based agriculture of 10%.

Many Nitrogen Use Efficiencies were higher this year than in previous years. This is due to higher agricultural yields and lower fertiliser use as a result of unusually good weather in 2022 for farming. Future years with more typical weather would likely show NUE values closer to previous years.

There have been broadly no major changes to NUE values calculated for previous years, however the SNBS calculations have received some methodological updates, which are outlined within the Revisions section of the SNBS.

The inherent uncertainties in the underlying data means that the SNBS may need to be revised in the future for purely technical reasons. Such revisions have the potential to affect all historic time periods referenced. Additionally, there will always be a variable level of uncertainty present due to the wide variety of data sources used, spread across a variety of administrative data, survey data and modelled data. The disparate methods will all have different levels of inherent uncertainty within them which means caution must always be taken when comparing between flows.