The World Health Organization (WHO) Regional Office for the Western Pacific recently launched an improved version of the All-Cause Mortality and Excess Mortality (ACM/EM) Calculator (2025) during an online webinar. This digital public good enables countries to analyze mortality trends, detect unusual patterns and strengthen preparedness for future health emergencies.
Originally developed in 2022 in collaboration with the University of California, Los Angeles to assess excess mortality during the COVID-19 pandemic, the tool has undergone significant enhancements. The updated version now incorporates mortality patterns from pre-, mid-, and post-COVID-19 pandemic periods, allowing users to assess the impact of other defined events such as epidemics, natural disasters or major health interventions.
In addition, the ACM/EM Calculator now offers:
- Subnational analysis: Users can upload data at provincial or district levels for localized assessments.
- Expanded statistical models: In addition to Negative Binomial Regression and five-year historical average, the tool now includes autoregressive integrated moving average (ARIMA), Poisson Regression and linear models to improve robustness.
- Enhanced interactive visualizations and customized report generation in PDF and HTML formats.
- Improved speed and performance for a smoother user experience.
The upgraded ACM/EM Calculator has been tested and positively reviewed by the Korea Disease Control and Prevention Agency (KDCA), the Japan Institute for Health Security (JIHS) and the Australian Institute of Health and Welfare (AIHW), confirming its readiness for wider adoption across the Region.
The ACM/EM Calculator strengthens multi-source surveillance, risk assessment and evidence-informed policy dialogue and decision making, while safeguarding national data sovereignty. All calculations can be performed locally – either in the browser or offline – ensuring that confidential data is not shared unless users choose to do so.
The updated ACM/EM Calculator was jointly developed by the Health Information and Digital Health unit of the Division of Data, Strategy and Innovation and by the Health Information Management Unit of the WHO Health Emergencies Programme of the WHO Regional Office for the Western Pacific and was supported by a voluntary contribution from the Government of the Republic of Korea, through its Ministry of Health and Welfare.
For further information, please contact the Health Information and Digital Health unit at wprohii@who.int