The first stamp issued in 1998 cost $.40 instead of the usual $.34 at the time. The extra 6 cents went for research - 70 percent to the Cancer Institute and 30 percent to the Department of Defense. The stamp has been reissued multiple times since, and has raised more than $86 million for breast cancer research.
https://www.nbcnews.com/health/women...-study-n879921