Table 1

Sample size of benchmark and follow up surveys

	Benchmark May 1997	Follow up 1 Nov 1997	Follow up 2 Nov 1998	Follow up 3 Nov 1999	Follow up 4 Nov 2000
Informants aged ≥18 years	6632	17 572	11 153	12 246	13 742
Total household enumeration aged ≥18 years	13 807	36 538	23 319	25 147	29 267
Survey respondents 18–40 years	1979	4197	2289	2277	2308
Nonsmoker respondents	781	1191	628	645	613
Smoker and recent quitter respondents	1192	2981	1646	1611	1675