The study found that 21.2 percent of Hoosiers said they regularly smoke cigarettes, a habit that costs the state almost $2.6 billion in productivity losses and $2.2 billion in health care costs each year.

"Burden of Smoking among Adults in Indiana," the report by the university's Global Health Institute, compiled data from 2010 Centers for Disease Control reports. The study concluded that, in terms of the percentage of the population that uses cigarettes, Indiana ranked 42nd worst among the 50 states and Washington, D.C.

"We have known for decades that smoking is counterproductive for our health and plays a major role for the spiraling health care costs facing both employees and their employers," said GHI Director Kerry Anne McGeary and Phyllis A. Miller, a professor of health economics, in a news release.

"When combined with our reports on obesity and asthma, on average Hoosiers have health issues and engage in health behaviors that put them at risk for future health conditions."

McGeary said an average of 9,700 deaths per year in Indiana can be attributed to smoking, and the habit is the leading cause of preventable death in the United States, accounting for one in five deaths or about 443,000 each year.

The study found that the percentage of current smokers in Indiana has dropped from about 29 percent in 1996 to 21.2 percent in 2010. About 60 percent of Hoosiers who smoke have tried to quit at least once, tying the national rate.

McGeary said anti-smoking policies -- such as the statewide ban passed by the Indiana General Assembly during the 2012 session -- combined with new tobacco taxes, anti-smoking campaigns and indoor clean air acts have played a role in reducing the number of people taking up the habit.

The Ball State study also found that smoking is more common among men than women, more prevalent in people 25 to 44 years old and more widespread in black adults, rather than white or Hispanic adults.