Michigan Compiled Laws, Chapter 500. Insurance Code of 1956 § 500.2110a

Sec. 2110a. If uniformly applied to all its insureds, an insurer may use factors in addition to those permitted by section 2111  1 for insurance if the plan is consistent with the purposes of this act and reflects reasonably anticipated reductions or increases in losses or expenses. This section does not affect benefits or obligations required under chapter 31.  2This section does not authorize an insurer to offer or prohibit an insurer from offering premium discount plans concerning any of the following: