Table 2.

Conditional Probabilities of Tobacco Use, by Class

	Frequent current smokers	Light current smokers	Former smokers	Nonsmokers
Class prevalence (%)	5.4	6.1	19.3	69.2
Ever tried cigarettes (1 or 2 puffs)
No	0.000	0.000	0.000	0.723
Yes	1.000	1.000	1.000	0.277
Age at initiation
Never smoked a whole cigarette	0.000	0.012	0.000	1.000
8 or 10 years old	0.295	0.101	0.232	0.000
11 or 12 years old	0.168	0.119	0.222	0.000
13 or 14 years old	0.237	0.387	0.324	0.000
15, 16, or 17 or years older	0.300	0.381	0.222	0.000
During the days that you smoked, how many cigarettes did you smoke per day (during the past 30 days)?
Did not smoke cigarettes during the past 30 days	0.000	0.000	1.000	1.000
Less than 1–1 per day	0.033	0.741	0.000	0.000
2–5 cigarettes/day	0.625	0.259	0.000	0.000
6 to more than 20 cigarettes/day	0.342	0.000	0.000	0.000
How many days did you smoke cigarettes, during the past 30 days?
0 days	0.000	0.000	1.000	1.000
1 or 2 days	0.000	0.541	0.000	0.000
3 to 19 days	0.265	0.443	0.000	0.000
20 to all 30 days	0.735	0.016	0.000	0.000
Ever smoked daily? (consecutively for at least 30 days)
No	0.188	0.861	0.956	1.000
Yes	0.812	0.139	0.044	0.000