Table 1

The distribution of year of death and year of latest follow-up

Observation period	Death confirmation		Latest follow-up date
Observation period	Number of deaths	%	With individual	%	Without individual	%
1960–1964	1	0.65	0	0	0	0
1965–1969	1	0.65	0	0	0	0
1970–1974	0	0	0	0	0	0
1975–1979	3	1.96	0	0	0	0
1980–1984	10	6.54	0	0	0	0
1985–1989	4	2.61	0	0	0	0
1990–1994	10	6.54	0	0	0	0
1995–1999	11	7.19	1	0.05	0	0
2000–2004	37	24.18	15	0.79	0	0
2005–2009	30	19.61	45	2.36	0	0
2010–2014	28	18.3	149	7.83	0	0
2015–2017	18	11.76	1694	88.97	1324	100
Total	153	100	1904	100	1324	100