Between 2.0 and 3.0.  In 20 years of reviewing Experience Modification Rates for clients we have never seen an Experience Modification Rate of 3.00 or higher.  We have heard anecdotes that we can't verify, but we've never seen it.  The Experience Rating Algorithm has safeguards to keep and Experience Modification Rate from rising to, say, a 10.00.  That would not just dramatically increase but also put employers out of business.  So, for example, one safeguard is the "state max."  It's different in every state but the state max limits the amount of a claim that counts against (raises) your Experience Modification Rate.  $400,000 is close to most maximums.  So, if you had a $1 million claim, only $400K would count against you while the remaining $600K would not.