Reference for https://api.erg.ic.ac.uk/AirQuality/Annualiser/Calculate/year={YEAR}/site={SITE}/backA={BACKA}/backB={BACKB}/backC={BACKC}/backD={BACKD}/species={SPECIES}/mean={MEAN}/Json

This returns the annualisation calculation!

Url: https://api.erg.ic.ac.uk/AirQuality/Annualiser/Calculate/year={YEAR}/site={SITE}/backA={BACKA}/backB={BACKB}/backC={BACKC}/backD={BACKD}/species={SPECIES}/mean={MEAN}/Json

HTTP Method: GET

Message direction	Format	Body
Request	N/A	The Request body is empty.
Response	Unknown	The Response body cannot be inferred.