What is excess mortality?

Statistics Netherlands (CBS) keeps track of how many people die in the Netherlands. Normally - without corona - an average of 2,900 people die per week. Depending on the time of year, this number is lower or higher. If you know how many people die on average in a certain month, you can also see the effect of, for example, the flu or a heat wave. Then more people die than average. We call this difference excess mortality. In this way, the effect of the virus is also visible in the statistics.

Excess deaths on the dashboard

In the graph 'Mortality per week' on the dashboard you see a light blue line. This shows the number of deaths you can expect based on the average of previous years. The figure can fluctuate: sometimes it is slightly lower and sometimes slightly higher than the average. You can see how big that difference normally is in the light blue strip. The orange line shows how many people died this year. If the orange line rises above the light blue strip, there is excess mortality.

Fewer deaths than expected

It may also be that fewer people die than you would expect based on the average. Then there is under-mortality. Under-mortality often occurs after a period of excess mortality. After a peak in a graph, there is usually a trough. This is because people who were already in poorer health die, for example due to the pandemic. The exact number of deaths in a period will only become clear later, when Statistics Netherlands publishes the figures based on cause of death.