Applications to the Commissioner for higher than prima facie premium rates shall be accompanied and supported by credible statistics. Approval of applications for increased rates shall depend on whether the requested rates are not greater than rates based on the standards in this chapter. On policies of credit involuntary unemployment benefit insurance for which the prima facie loss ratio exceeds 58 percent, the rate shall be determined by the formula: Premium rates for credit involuntary unemployment benefit insurance determined under this regulation shall be rounded to three decimal places per $10 of monthly benefit payable.