Most WC rates are lowered with every dollar saved on claim costs. The quetion is, "how much?"
Claim costs are used to calculate the company's experience modification factor. Lower EMFs produce lowered rates. You can look over your company's loss history and calculate premium savings realized by eliminating a certain claim, for example, or types of claims through investments in safety resources and then weigh the cost versus the savings in WC insurance premiums. It's a fairly complicated calculation if your not familiar with it, but you can ask your insurance carrier for help.