Measurements > Spirometry displays your data as a breakdown of the ratio of POST FEV1/FVC.
FEV1 is the forced expired volume in one second
FVC is the forced vital capacity
FEV1/FVC provides an index of airflow limitation; a value < 0.7 indicates limitation
The breakdown is shown as



Spirometry Mappings with clinical systems


The Spirometry mappings are provided in the 'General Data Mappings' Appendices under Measurements for each clinical application.