Epidemiology of perforated peptic ulcer: Age- and gender-adjusted analysis of incidence and mortality

Figure 4 Change in prevalence of daily smokers in Norway. A: The time trend of daily smokers over time in the Norwegian population aged between 16-74 years, showing a decline over time for each gender; B: The distribution of smokers according to age groups and gender for the fiscal year 2011. Data are reproduced and presented from the Norwegian Directorate of Health (http://www.helsedirektoratet.no, accessed October 5, 2012).