(a) A rate filed under this subchapter is not excessive unless the rate is unreasonably high for the coverage provided and a reasonable degree of competition does not exist with respect to the classification to which the rate is applicable.
(b) A rate filed under this subchapter is not inadequate unless the rate is insufficient to sustain projected losses and expenses or the rate substantially impairs, or is likely to substantially impair, competition with respect to the sale of the product.