Farm Business Survey 2021-22: Farm level emissions and nitrogen usage: Methodology

Accuracy and Reliability

This section discusses how accurately and reliably these statistics portray reality.

June Agricultural Census Area Estimates

Data quality and assurance measures for the June Agricultural Census are available at Scottish Agricultural Census: results - gov.scot (www.gov.scot)

The Farm Business Survey

Data quality and assurance measures for the Farm Business Survey and its official statistical outputs are available at Scottish farm business income (FBI) - gov.scot (www.gov.scot).

As a sample survey, results are subject to a degree of uncertainty. More detailed breakdowns of the sample result in relatively low sample sizes and an increase in uncertainty. For example in representing overall national averages by farm type.

Greenhouse gas emission and nitrogen estimates

These data are designated as experimental statistics as they are still in development, with a potentially wider degree of uncertainty in the resulting estimates as the methods and processes are established and verified.

To demonstrate the variability in the data the average (median) result is presented along with the upper and lower quartiles of the data. Results are not directly comparable to results published on farm income for the average (mean) farm.

There are limitations to the emissions estimate methodology. Different results may be obtained using different carbon calculators or different methods, for example using an inventory approach. More information is included under Greenhouse gas (GHG) emission estimates methodology.

There are limitations to the nitrogen estimate methodology. Nitrogen estimates are based on standard estimates of nitrogen content in all farm inputs and outputs where possible. Nitrogen estimates are not made for organic farms, which means a small proportion of the sample are excluded. More information is included under Nitrogen use estimates methodology.