45 CFR § 154.200 - Rate increases subject to review.
(a) A rate increase filed in a State, or effective in a State that does not require a rate increase to be filed, is subject to review if:
(1) The rate increase is 15 percent or more applicable to a 12-month period that begins on January 1, as calculated under paragraph (b) of this section; or
(2) The rate increase meets or exceeds a State-specific threshold applicable to a 12-month period that begins on January 1, as calculated under paragraph (b) of this section, determined by the Secretary. A State-specific threshold shall be based on factors impacting rate increases in a State to the extent that the data relating to such State-specific factors are available by August 1 of the preceding year. States interested in proposing a State-specific threshold greater than the Federal default stated in paragraph (a)(1) of this section are required to submit a proposal for approval of such threshold to the Secretary by August 1 of the preceding year, in the form and manner specified by the Secretary.
(b) A rate increase meets or exceeds the applicable threshold set forth in paragraph (a) of this section if the average increase, including premium rating factors described in § 147.102 of this subchapter, for all enrollees weighted by premium volume for any plan within the product meets or exceeds the applicable threshold.
(c) If a rate increase that does not otherwise meet or exceed the threshold under paragraph (b) of this section meets or exceeds the threshold when combined with a previous increase or increases during the 12-month period preceding the date on which the rate increase would become effective, then the rate increase must be considered to meet or exceed the threshold and is subject to review under § 154.210, and such review shall include a review of the aggregate rate increases during the applicable 12-month period.