Actuaries Climate Index Winter 2017–18 Data Released

Actuaries Climate Index^® Winter 2017–18 Data Released

ACI Five-year Average of Climate Extremes Continues Upward

Washington, D.C., Arlington, VA, Schaumburg, IL, and Ottawa, ON (November 15, 2018)—Organizations representing the actuarial profession in Canada and the United States report new Actuaries Climate Index^® (ACI) data, showing that the five-year moving average of climate extremes and sea level across the two countries reached a new high with data released for winter 2017–18.

“Rising sea levels and more frequent high temperatures are sustaining the long-term trend of higher ACI values,” says Doug Collins, chair of the Climate Index Working Group, which helped develop the index.

Measured with the new winter 2017–18 data included, the five-year moving average of the ACI increased to 1.23, compared to 1.19 in fall 2017, the last period with available data from the ACI. The elevated index value reflects continued deviation of climate and sea level extremes from historical levels for the two countries.

The decline in the last seasonal ACI value did not keep the five-year moving average from rising. “The seasonal index value for winter 2017–18 was 1.08, compared to 2.00 in the fall, and an average of 1.83 for the previous nine seasons combined, but still well above any of the seasonal values in the reference period, and it replaced a much lower value in the moving five-year average,” says Collins.


The ACI is based on analysis of seasonal data from neutral, scientific sources for the six index components collected since 1961. The index measures changes in extremes of high and low temperatures, high winds, heavy precipitation, and drought, as well as changes in sea level, expressed in units of standard deviations from the mean for the 30-year reference period of 1961 to 1990 for the United States and Canada combined and by region. “Actuaries view the five-year average index as a much more stable measure of the direction of the index than the fluctuating seasonal values,” says Collins.

The index, jointly sponsored by the American Academy of Actuaries, the Canadian Institute of Actuaries, the Casualty Actuarial Society, and the Society of Actuaries, is designed to provide actuaries, public policymakers, and the general public with objective data about changes in the frequency of extreme climate events over recent decades.

Updated values are posted quarterly on ActuariesClimateIndex.org as data for each meteorological season becomes available. The organizations are also in the process of developing a second index, the Actuaries Climate Risk Index, to measure correlations between changes in the frequency of extreme events as measured by the index and economic losses, mortality, and injuries.

About the Sponsoring Organizations
The American Academy of Actuaries is a 19,500+ member professional association whose mission is to serve the public and the U.S. actuarial profession. For more than 50 years, the Academy has assisted public policymakers on all levels by providing leadership, objective expertise, and actuarial advice on risk and financial security issues. The Academy also sets qualification, practice, and professionalism standards for actuaries in the United States.

The Canadian Institute of Actuaries (CIA) is the national, bilingual organization and voice of the actuarial profession in Canada. Its 5,500 members are dedicated to providing actuarial services and advice of the highest quality. The Institute holds the duty of the profession to the public above the needs of the profession and its members.

The Casualty Actuarial Society (CAS) is a leading international organization for credentialing and professional education. Founded in 1914, the CAS is the world’s only actuarial organization focused exclusively on property and casualty risks and serves over 8,000 members worldwide. Professionals educated by the CAS empower business and government to make well-informed strategic, financial and operational decisions.

With roots dating back to 1889, the Society of Actuaries (SOA) is the world’s largest actuarial professional organization with more than 30,000 actuaries as members. Through research and education, the SOA’s mission is to advance actuarial knowledge and to enhance the ability of actuaries to provide expert advice and relevant solutions for financial, business and societal challenges. The SOA’s vision is for actuaries to be the leading professionals in the measurement and management of risk.