Table 1.

Joint frequency of smoking stages (percent) across waves I and III among original population of size n = 19 895 953.^*

	Wave III smoking
Wave I smoking	Never smoked	Puffer	Light	Occasional	Regular	Ex-smoker	Row total
Never smoked	20.84	6.48	8.66	2.97	5.16	0.06	44.17
Puffer	2.20	3.54	3.66	1.21	2.34	0.02	12.98
Light	1.43	2.28	5.17	1.81	3.01	0.08	13.77
Occasional	1.41	0.86	3.83	3.35	6.78	0.08	16.31
Regular	0.44	0.05	0.19	1.49	7.62	0.02	9.81
Ex-smoker	0.19	0.09	0.64	0.59	1.43	0.02	2.96
Column total	26.51	13.29	22.15	11.43	26.34	0.28	100.00

^*Figures in bold represent wave III responses incompatible with wave I self-reports.