Tobacco production has continued to shift  from high-  to low- and  medium-  Human  Development  Index  (HDI)  countries over the past 50  years. Many consider  tobacco  a cash  crop, but  studies  conducted  in  multiple  countries  have found that tobacco farmers are often stuck in a cycle of debt that the tobacco industry  perpetuates  in  its  relationships with these farmers. In addition, as many as 16 countries use child labor in the production of tobacco.