Cook County Board President Toni Preckwinkle dropped a proposed tax of 5 cents per bullet because the tax in some cases would have cost more than the ammunition price itself, according to an article from the Chicago Tribune.

However, Preckwinkle is keeping a plan to tax firearms to help defray healthcare expenses associated with the high rate of gun violence across Cook County, especially the city of Chicago. If approved by the board, the third most populous county in the U.S. could be the first major U.S. metropolitan area to impose a tax as a form of gun control, according to the Law Center to Prevent Gun Violence.

“It is very important to us to tax guns because we know that guns are the source of the incredible violence we have in our neighborhoods,” says Preckwinkle at a news conference on Wednesday. She said 29 percent of the guns used in Chicago crimes were purchases legally in suburban Cook County, the Tribune reports.

So far this year, there have been 440 murders in Chicago.