80,000 to 100,000 children begin smoking every day, roughly half of whom live in Asia. Half of those who begin smoking in adolescent years are projected to go on to smoke for 15 to 20 years. As of 2019 in the United States, roughly 800,000 high school students smoke.The World Health Organization (WHO) states that "Much of the disease burden and premature mortality attributable to tobacco use disproportionately affect the poor". Of the 1.22 billion smokers, 1 billion of them live in developing or transitional economies. Rates of smoking have leveled off or declined in the developed world. In the developing world, however, tobacco consumption is rising by 3.4% per year as of 2002.The WHO in 2004 projected 58.8 million deaths to occur globally, from which 5.4 million are tobacco-attributed, and 4.9 million as of 2007. As of 2002, 70% of the deaths are in developing countries. As of 2017, smoking causes one in ten deaths worldwide, with half of those deaths in the US, China, India and Russia. Psychology
Takeup
Most smokers begin smoking during adolescence or early adulthood. Some studies also show that smoking can also be linked to various mental health complications. Smoking has elements of risk-taking and rebellion, which often appeal to young people. The presence of peers that smoke and media featuring high-status models smoking may also encourage smoking.
Within the 14- to 15-year-old age group, one peer pressure variable emerged as a significantly more important predictor of girls than boys smoking. It is debated whether peer pressure or self-selection is a greater cause of adolescent smoking. Psychologist Hans Eysenck (who later was questioned for nonplausible results
 and unsafe publications) developed a personality profile for the typical smoker. Extraversion is the trait that is most associated with smoking, and smokers tend to be sociable, impulsive, risk taking, and excitement seeking individuals. Persistence
The reasons given by some smokers for this activity have been categorized as addictive smoking, pleasure from smoking, tension reduction/relaxation, social smoking, stimulation, habit/automatism, and handling. There are gender differences in how much each of these reasons contribute, with females more likely than males to cite tension reduction/relaxation, stimulation and social smoking.Some smokers argue that the depressant effect of smoking allows them to calm their nerves, often allowing for increased concentration. However, according to the Imperial College London, "Nicotine seems to provide both a stimulant and a depressant effect, and it is likely that the effect it has at any time is determined by the mood of the user, the environment and the circumstances of use. Studies have suggested that low doses have a depressant effect, while higher doses have stimulant effect." Patterns
A number of studies have established that cigarette sales and smoking follow distinct time-related patterns.