A tale of two mortality decades – UPDATED

This post updates the tale of New Zealand’s mortality to 2020, the year of the Covid-19 pandemic.

A previous post told the tale of mortality in Aotearoa for the years 2000-2010 and 2010-18.  It showed how death rates were falling, which means mortality is improving, adding to longer lifespans. In the second period, the fall in death rates began to stall, as has happened in other countries, across nearly all age groups over age 50, for males and females.

The chart below updates with the most recent mortality data to 2020. A significant improvement in mortality rates in 2020, the Covid year, is visible in the downtick of the trend lines of age-specific death rates, especially at the oldest ages.Age specific death rate trend to 2020

The improvement in 2020 was still not enough for the improvement over the decade 2010-2020 to catch up with that seen in 2000-10.  The same tale of two mortality decades – fast, then slow mortality improvement – holds.

Male mortality 2 decades to 2020

Female mortality 2 decades to 2020

For both males and females over age 50, the rate of improvement has been noticeably reduced in the later period, except for females aged 90 and over.  There is even a small worsening of mortality rates in the second period for females aged 55-59. However, the trends are still a reduction in mortality rates, which means life expectancy continues to increase.

The conclusion is the same as the previous tale. Average lifespans are getting longer, just not as fast as they once were. 

All calculations on data from Stats NZ Age-specific death rates by sex, December years (total population) Downloaded 20 June 2021.  Trend lines are calculated as the basis for finding rates of change as raw data has year-by-year volatility, but the shapes of the annual rates of change based on raw data are similar.

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