Any investment required to meet minimum quality ratings by the Insurers Investment Act shall be subject to the following categories:

(1) Category 1. Any investment subject to this subdivision shall have a 1 designation from the Securities Valuation Office. If the Securities Valuation Office does not rate the investment in question but does rate an obligation of the obligor having a priority equal to or lower than the investment in question, the insurer may apply such rating to the investment. If the Securities Valuation Office does not rate the investment in question or an outstanding obligation of the obligor having a priority equal to or lower than the investment in question, the investment shall have a minimum quality rating of A3 by Moody's Investors Services, Inc., A- by Standard and Poor's Corporation, or the corresponding investment grade rating from any nationally recognized statistical rating organization recognized by the Securities Valuation Office; and

(2) Category 2. Any investment subject to this subdivision shall have a 1 or 2 designation from the Securities Valuation Office. If the Securities Valuation Office does not rate the investment in question but does rate an obligation of the obligor having a priority equal to or lower than the investment in question, the insurer may apply such rating to the investment. If the Securities Valuation Office does not rate the investment in question or an outstanding obligation of the obligor having a priority equal to or lower than the investment in question, the investment shall have a minimum quality rating of Baa3 by Moody's Investors Services, Inc., BBB- by Standard and Poor's Corporation, or the corresponding investment grade rating from any nationally recognized statistical rating organization recognized by the Securities Valuation Office. If the obligor of an investment is authorized by, established by, or incorporated under the laws of Canada or any province thereof and the Securities Valuation Office does not rate the investment in question, the minimum quality rating shall be BBB (low) by the Dominion Bond Rating Service, B++ by the Canadian Bond Rating Service, or the corresponding rating of any successor organization approved by the director.