Table 2 Absolute values of FEV1 in litres calculated as predicted FEV1 (at average height) minus specified deficit.

Age (years)	Predicted FEV1	Deficit (litres) (increase in odds for risk of breathlessness)
		0.367 (1.5)	0.627 (2.0)	0.993 (3.0)
30	4.122	3.755	3.495	3.129
45	3.644	3.277	3.017	2.651
60	3.080	2.713	2.453	2.087