Except as otherwise provided in §§ 38.2-3207 and 38.2-3208, all adjusted premiums and present values referred to in §§ 38.2-3202 through 38.2-3205 shall for all policies of ordinary insurance be calculated on the basis of the Commissioners 1941 Standard Ordinary Mortality Table. However, for any category of ordinary insurance issued on female risks, adjusted premiums and present values may be calculated according to an age not more than three years younger than the actual age of the insured and the calculations for all policies of industrial insurance shall be made on the basis of the 1941 Standard Industrial Mortality Table. All calculations shall be made on the basis of the rate of interest, not exceeding 3 1/2 percent per year, specified in the policy for calculating cash surrender values and paid-up nonforfeiture benefits. However, in calculating the present value of any paid-up term insurance with any accompanying pure endowment, if any, offered as a nonforfeiture benefit, the rates of mortality assumed may be not more than 130 percent of the rates of mortality according to the applicable table. For insurance issued on a substandard basis, the calculation of any adjusted premiums and present values may be based on any other table of mortality specified by the insurer and approved by the Commission.