• @DaveMA
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    24 months ago

    I’d also like to point out that while births has gently fallen over the past few years, the " lowest annual natural increase since World War II" that the article mentions may have been related to the spike in deaths since COVID: https://www.stats.govt.nz/topics/births-and-deaths

    • @eagleeyedtiger
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      4 months ago

      I’m not a stats person at all so I may be confused… but the article is using figures from 2023 and that graph only goes to 2022. They say the natural increase was only 19071 last year, while deaths were ever so slightly lower than 2022. Natural increase in 2022 was 20313. Were we still having a lot of COVID related deaths last year?

      Edit:

      This combination - fewer births and more women of child-bearing age - resulted in a record-low fertility rate of 1.56 births per woman.

      The total fertility rate has been below the replacement rate of 2.1 births per woman since 2013. The replacement rate is the number of births women need to have on average for the population to replace itself in the long term, with no migration.

      Apparently we’ve been below the replacement rate since 2013!?

      • @DaveMA
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        24 months ago

        Were we still having a lot of COVID related deaths last year?

        I thought so, but it seems our baseline is now only a couple of deaths per week. The graph I linked doesn’t have 2023 data, and I can’t seem to find any, so I’d be curious to see if deaths fell last year or stayed high.

        Apparently we’ve been below the replacement rate since 2013!?

        Weird. We have more births than deaths, so I’m curious about this. Any experts that can weigh in on the complexities of this? Is it something to do with people living longer so the low birthrate doesn’t show in the statistics of people currently dying, or something like that?

        • @eagleeyedtiger
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          24 months ago

          37884 deaths in 2023 vs. 38574 in 2022. So a small decrease it looks like.

          • @DaveMA
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            24 months ago

            Ah nice. Digging back through the years, the spike doesn’t feel as big anymore. For sure, the 2022 increase over 2021 of about 3,600 deaths is an increase not seen ever before in this dataset (which starts after WW2 was already well over), but in recent years the increase has been in the ballpark of 500 extra deaths per year (jumping around a lot in individual years). If we start from say 2018, then we expect about 2,500 more deaths in 2023 vs 2018. 2018 had about 33,000 deaths, so 2023 we would expect about 35,500 compared to the actual 37,800. Hmm, ok 2,000 more than expected.

            And if we look at the extras from the year before, but minus the missing people from all the ones that didn’t die in 2020 when we were in lockdown, the difference of about 4,000 gets us back in the ballpark of the number of people who have died from COVID.

            When I started writing this I thought I was uncovering extra deaths from an unknown cause, but nah seems it’s just COVID.

        • @eagleeyedtiger
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          24 months ago

          Ok I found this with some googling, but I think I’m not smart enough to understand it:

          The total fertility rate in a specific year is defined as the total number of children that would be born to each woman if she were to live to the end of her child-bearing years and give birth to children in alignment with the prevailing age-specific fertility rates. It is calculated by totalling the age-specific fertility rates as defined over five-year intervals. Assuming no net migration and unchanged mortality, a total fertility rate of 2.1 children per woman ensures a broadly stable population. Together with mortality and migration, fertility is an element of population growth, reflecting both the causes and effects of economic and social developments. The reasons for the dramatic decline in birth rates during the past few decades include postponed family formation and child-bearing and a decrease in desired family sizes. This indicator is measured in children per woman.

          • @DaveMA
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            24 months ago

            Yeah I don’t know. Like I get it at a conceptual level.

            It basically says that they work out the fertility rate by dividing the number of women by the number of babies. They say they do it in 5 year blocks, I guess this accounts for say lots of kids or lots of old women skewing the numbers when they don’t have babies.

            As for why we have 38,000 deaths and 59,000 births and this is below the replacement rate, I start to feel like I understand but then decide I don’t. The best answer I’ve found is a suggestion that births per women below 2.1 doesn’t necessarily mean a shrinking population, because of the distribution of women of various ages may mean many women of childbearing age (say, through immigration) can cause the population to grow despite births per women being below 2.1.

            • @eagleeyedtiger
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              24 months ago

              It’s too late and I can’t wrap my head around it. Is there some effect from what the deaths and births are? As in it’s not necessarily old people dying and not all births are female which would then further impact the fertility rate?

              I understand that the 2.1 replacement rate needed is assuming no migration. There will almost always be migration though.

              I think I need to sleep and stop trying to understand this

              • Exocrinous
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                24 months ago

                Low fertility rates mean the death rate will be higher than the birth rate in the future. But not necessarily right now.

                Imagine I build 100 robots, who will each live precisely 100 years. One robot chooses to build a replacement for itself, the rest do not. For 100 years, the death rate will be 0, and the birth rate will be 1. So more births than deaths. But the fertility rate is 0.01, so in 100 years the first generation will all die. Today the birth rate is higher, but low fertility means it’ll be lower eventually.