Experience modification rate
Your experience modification rate, called your EMR, your mod, or your x-mod, is a multiplier applied to your workers' compensation premium. A rating bureau, NCCI in most states, calculates it once a year from your own payroll and claims over a three-year window, then compares your actual losses to what's expected for a contractor your size doing your kind of work. A 1.00 means your claims history looks average. Above 1.00, you pay more than a contractor with an average record. Below 1.00, you pay less. The same number is also used well beyond your own premium. Many general contractors, owners, and public agencies use an EMR below 1.0 as a cutoff for who gets to bid a job at all, and your surety looks at the same number when deciding your bonding capacity. Because the rating window covers three years and the year that just ended isn't included yet, the number you're looking at today reflects claims and payroll from further back than it feels like, which is part of why an EMR can stay elevated well after the problem behind it is fixed. Every input into the calculation, your payroll, your claims, your class codes, is a number someone entered, and none of it is self-correcting.
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Is your mod right?
Most contractors have never had the worksheet compared to the loss runs and payroll behind it. See what your mod is costing you, or get on the list for a full verification.