• This analysis by S&P Global Market Intelligence is limited to publicly available rate filings submitted to state insurance regulators.
• Rate filing information is sourced from the System for Electronic Rate and Form Filing documents.
• States employ a variety of rate regulation mechanisms such as prior approval, modified prior approval, file and use, and use and file. Form filing laws govern the type of policy form regulation used by a state and may not require explicit approval by regulators prior to insurers using the new rate.
• This analysis is based on when a rate filing is "disposed" by a state regulator and does not take into account when the new rate became effective for new and renewal business. In some instances, new rates have been in effect prior to the particular month filings are "disposed" by regulators.

Increases by The Progressive Corp. continued to be among the most-notable private auto insurance rate changes for the month of March.

Progressive received approval for 36 rate increases across 13 states during the month, combining for $511.9 million in additional calculated premiums written. A pair of rate hikes approved by Minnesota are expected to account for $142.3 million, or 27.8%, of the expected premium increases.

State Farm also boosts rates

State Farm Mutual Automobile Insurance Co., the largest private auto insurance underwriter in the U.S., also made some significant private auto rate increases during March.

State Farm subsidiaries received approval for 17 rate increases across nine states in the month. Combined, those rate hikes could push the insurer's premiums written up by $183.7 million. More than 60% of the calculated premium increase is expected to come from two rate-hike requests approved on March 23 by Pennsylvania regulators. Those new rates are set to go into effect on May 26 on both new and renewal bases.

Amica's 5 rate reductions

On the other side of the spectrum, Amica Mutual Insurance Co. received approval for five rate cuts which, when combined, could reduce the insurer's premiums by $4.3 million.

This analysis included 609 private auto rate filings approved in March, of which 412 were rate increases and 25 were rate decreases. The remaining filings did not have any impact on written premiums.