[Serious] Stats people: can you tell me why there’s fewer 45-49 year olds than say, 50-54 year olds, or 40-44 year olds?

15 comments

1. The US has the same dip at 45-49, so I don’t think the answer will be UK specific.

2. It likely correlates with affordability. If you look at a chart of interest rates historically that was a period of 10-17%.

3. I am 48, in my sample size of one, I think there is plenty of me.

4. 1973–1975 recession

5. The combined sexual magnetism of Slade and the Bay City Rollers was so powerful that for a time in the mid seventies a large swathe of the female population physically couldn’t have had sex with someone not in those bands even if they wanted to. For the rest they could only become sexually aroused if a poster of David Essex or Bryan Ferry was on the bedroom wall.

   To this day men in their 60s and 70s shudder when they hear ” It’s Christmas!”

6. Larger or smaller numbers of babies tend to be born in waves, such as the post-war baby boom. The bumps in the population pyramid are those babies getting older, moving up the chart like a large piece of food travelling down a snake.

7. Birth control introduced in the early 60s brought down the birthrate. From ’67 – 77 they went into freefall. That’s people aged 59-46 now. There was also the Abortions act of 1968.

   Have a look at historic birthrates.. there were two ‘mini booms’ between 78 and now resulting in higher cohort numbers.

   https://www.ons.gov.uk/peoplepopulationandcommunity/birthsdeathsandmarriages/livebirths/bulletins/birthsummarytablesenglandandwales/2022

8. 45 to 49 corresponds to births between 1973 and 1977 which was the end of a steady decline in UK birth rate that started in the mid- to late-60s.

   You have the widespread availability and acceptance of the pill from the late 60s, becoming free in 1974 and the legalization of abortion in Great Britain in 1967 giving women much greater control of their fertility. Add to that the particular economic stresses of the mid 70s and it’s no wonder this was a low point for child bearing.

9. The post-war baby boom was over and the Boomers hadn’t started having babies yet. There weren’t so many of the War Generation to have babies.

   Add the availablity of contraception, and you end up with a drop.

10. Can anyone explain the United Arab Emirates stats?

11. The government was concerned about over population because of rapid population growth in the 1960s and so in the 1970s family planning services, including contraception and abortion were made available on the NHS regardless of age of marital status in an effort to stabilise the population.

12. Just a mirror from previous peaks and troughs in numbers of births?

13. 2.8% of 20-24 females in UK vs 1% of 20-24 females in Ukraine. I wonder what percentage of those 2.8% in UK are ukranians 😂

14. Not 100% – but there’s such a thing as a war ‘shadow’ in that, where there is a situation of population decline due to an event- say- war, famine, natural disaster- supproessing births for say 5-10 years, there tends to be a ‘shadow’ of this like 25 years later.

    This is the squeeze replicated in the next generation, as there are less fertile aged women, and to a lesser extent men to have babies. Because there were less born during the bad times 20- 30years ago.

    Looking at this pyramid, this might be evident in the 65-70 age group (ww2? Rations?). The 45-49year odds, and 20-24years – my basic point being their isn’t just one dip- it repeats like the narrow bits in the caterpillar.

    It’s the repeating effect of something- maybe the war and rations period?

15. World War 2 caused a baby boom – 1942 thru 1952.

    And after every boom there is the inevitable bust – meaning that there simply weren’t as many children born in the 50s as there were in the 40s and 60s…

    You see, that boomer generation grew up and had their children between 1964 and 1972 and those children are now 50-54 years old.

    Congratulations, you’ve just discovered GenX!

    (Conversely, someone who is 40-49 was born between 1974 and 1983 to parents who were 20 to 35 at the time. So their parents would have most likely been born some time in the mid 1950s, by which time the baby boom effect was fading.)

    I’m the classic genXer btw. Born in 1968 to parents who were born in 1943.