A Matter of Life & Death: The impact of declining fertility rates; the re-birth of a dataset buried for 50 years; and why you should call your baby Nigel.

Statistically Speaking

In this episode Miles is joined by Dr James Tucker and Sarah Caul MBE to talk about how and why the Office for National Statistics count births and deaths, and what current fertility trends might mean for the future population. They look at the impact of popular culture on the most common baby names in England and Wales, and discuss the new significance of a dataset that was itself buried for 50 years.

Transcript:

MILES FLETCHER

I’m Miles Fletcher and this episode of ‘Statistically Speaking’, the official ONS podcast, is literally a matter of life and death. Specifically how and why we count births and deaths and what those numbers are telling us. We'll talk about the possible impacts of declining fertility rates in the UK and of children being born to older parents. And at the other end of life we'll look at the new significance of a dataset that was itself almost buried for 50 years

I'm joined here at ONS by two people who lead on all our data around births and deaths - Head of Analysis in our health and life events teams, James Tucker, and our very own Head of Mortality, Sarah Caul MBE, honoured for her work during the pandemic about which we will talk later.

Starting with you then James, at the beginning as it were, with births - how does the ONS gather information about the number of children being born in England and Wales week in, week out? JAMES TUCKER So the registration of births is a service that's carried out by local registration services in partnership with the general register office in England and Wales and the good thing about this, from the perspective of having a really nice complete dataset, is that birth registrations are actually a legal requirement, giving us a really comprehensive picture of births in the countries. MF So we gather the numbers, we add them up, what do we do with the information then? JT So there's a couple of ways that we look at the data. One is to simply look at the number of births per year. So for example, we're looking at about 600,000 births per year at the moment. But an alternative approach is to use what we call the ‘total fertility’ rate, which is basically the average number of live children that women might expect to have during their childbearing lifespan. So it's a better measure than simply looking at the trends in the number of births because it accounts for changes in the size and age structure of the population. MF So it has a sort of multi-dimensional value then statistically that you can use to infer various things about the age at which people are likely to have children, and how many they're likely to have. JT That's exactly right. So we've seen some changes in the total fertility rate in recent years. So if you've heard the expression 2.4 children as describing the average number of children per family it's now considerably lower than that. In fact, it hit a record low in 2020 when the total fertility rate was 1.58. MF That's a sharp decline. In fact, though, you've got to go as far back as 1970, when the current series began, that's when it really was 2.4. What's really striking is if you look at that graph, the decline that happened between 1970 and about 1977 - very sharp decline there. Do we know what happened during that period? What were the factors driving that particularly? JT I think there can be all sorts of socio-economic factors affecting the fertility rate: improved access to contraception, reduction in mortality rates of children under five, which can result in women having fewer children. And also, more recently, as we've seen the average age of mothers going up, we might see some lower levels of fertility due to difficulties conceiving because of that postponement in childbearing. MF Sarah, I can see you want to come in on this. SARAH CAUL So my mother had three children by the time she was 30, and growing up I would just assume that that was the route I was going to take because it was what I've known. I am now 31 and I think if I was pregnant, that thought would scare me. I don't think I've grown up enough to have a child. I’m a dog mum, but those don't come into the statistics. MF So there was a bit of fanciful talk about people in lockdown finding - how should we put it delicately? - you know, things to do with their time, and that might lead to a boom in births. But that didn't really transpire? JT The increase in 2021 would actually coincide with conceptions across the second and third lockdowns. So yes, there was some speculation that people may have had enough of board games and were occupying their times in other ways, but I think it's actually more likely that it's a result of people delaying having children earlier on in the pandemic because of the uncertainty that was around at that point. And then towards the end of 2020 people had moved on from that and we saw a bit of an increase. MF Nonetheless though, historic data shows that there is a most common time of the year for conceptions to take place and that has something to do with the festive period, doesn't it? JT That's right. So the most common birthday is generally - almost always in fact - towards the end of September. So it doesn't take a statistician to work out that means the most popular time to conceive is over the Christmas and New Year periods. So that could be due to the Christmas festivities, but it might be also be something a bit less romantic than that. Some people, for example, might consider that there's an advantage to children being older in their year in school for example. MF The ONS also publishes the list of most popular baby names every year, and it is apparently one of the most downloaded and most popular bits of content on the ONS website. James, a lot of people scoff at this as an exercise. Is there any value in this list of baby names? Or is it something the ONS just produces because people like it? JT As you say it is one of our most popular releases and I think people use it to inform their own choices of names, and it can also tell us some really interesting things about culture in the country at the time. The top of the league table hasn't been that interesting, to be honest. So Oliver and Olivia have been the most popular names for the last few years, but it's beneath that that there's some really interesting trends emerging. So there's always a lot of interesting names that are going extinct. For example, last year, it was picked up a lot in the press about the name Nigel, which joined the list of critically endangered names like Gordon, Carol and Cheryl, and we do also see some really interesting influences of popular culture. And also royal babies always have a big influence. Some of the interesting ones from the last few years - we've seen some more Maeves and Otis’, which are characters from the TV series ‘Sex Education’, and even some Lucifers from the series of the same name. But generally you'd expect there to be positive associations with baby names so you do almost always see an influence of royal babies - we've already seen that with George but might be predicting a rise in Archies with Prince Harry’s son. MF And it’s quite interesting, seeing the cyclical thing with names that you might have associated with previous generations coming back into popularity, and Archie is a great example of that, isn't it? Sarah was one of the most popular girls names for a long time, certainly in the 80s and the 90s. But Sarah it's dropped out of the top 100 altogether. SC It has dropped down, but there's a Sarah in every single generation in my family. I think we're all named after each other. So my family is doing its best to keep it alive. JT Just a bit of a question for you. Where would you put the name Miles in the ranking? MF Well, it’s probably not in the top 100 James. JT Yeah, I'm afraid it's not quite top 100 material, but it is number 144. There were 390 Miles in 2020. And it's actually been on a bit of a roll recently. So that's the highest ranked it's been since 2002. MF Perhaps it’s the growing popularity of this podcast James, or maybe something else at work. Anyway... One thing worth noting about this before we move on, it should be pointed out that producing the baby names list is not an expensive exercise for the ONS. JT No, the data is very straightforward to collect. It's just a matter of compiling it into something that can be easily accessible and interesting for people to look at. MF And it's also one of the reasons that we don't compare the spelling of different names, because there's this long running thing isn't there about how if you added up the different spellings of the name Muhammad, then that would be the most popular boys name in England. That's not something the ONS does because, quite simply, we're just seeing the spelling that people enter on the system. JT Yeah, that's exactly right. And I think increasingly that could become even more of a task to compile those, because we're seeing an increasing use of shortened versions of names or alternative spellings. And if we were to try to compile those into one then that would definitely increase the time that we spent on it. MF Well, there you are, everything you need to know about baby names and - more seriously - the measurement of births and fertility. Plenty more information of course on the ONS website. With that, we must turn to the other end of life, and that is measuring deaths - a topic which has been very much in the news for the last couple of years since the outbreak of the pandemic. Right at the centre of that has been my colleague Sarah Caul, who's sat with us this afternoon. Sarah, you're recognised for your achievements during that period with an MBE, official honour, which you collected from Windsor Castle. SC It was definitely very surprising. I wasn't expecting it, but I'm very thankful for it. It's quite a proud moment in my life. If you ever see my mum, she'll just scream at you: “My daughter’s got an MBE”, so that's always nice. MF Recognised now then as an authority in this area - it's fair to say that the ONS was publishing this list of weekly deaths very quietly, almost unnoticed, for many years. And then of course, sadly, that changed at the start of the pandemic. SC With ‘weekly deaths’ it did have a small audience, to the point where they were considering actually not publishing it anymore. Pre-pandemic it wasn't a very large part of my job, because it was just something very quick and easy to do. My main analysis would be on annual data - we release annual data the summer after the end of the reference period. We would look at different causes of death and see where we could investigate further to help monitor the picture of what people are dying from, and if that can be prevented. MF That all changed of course March / April 2020 with the arrival of COVID-19. SC We started quite early thinking of what we could do with COVID and we added just one line into the spreadsheet, which was the number of deaths. It went from something like five to over 100 in one week and we were like “okay, we have to do a lot more of this now”. It just grew bigger and bigger because we were having more and more deaths and we needed to get out, as quick as possible, as much information as we could. We would be doing something that would usually take us months to do in a matter of days, every week. And we're actually still doing it to the same level now because we are still seeing COVID death - it hasn't completely gone away. MF Incredible demand for information from government, from everybody, of course - desperately concerned about what was happening. There was suddenly this incredible focus and attention, and huge pressure, on you to get those numbers out very quickly. SC Those first few months were quite a blur, because we were publishing weekly and monthly and were constantly adapting and constantly trying to figure out what people were interested in seeing. And getting that information out into the public domain is probably the most challenging time that I've had here. I don't think I've ever worked at that pace before. But we have got so many experts in the health analysis and life events area that we're in. We had expert coders, experts in different causes of death. It was great to see everybody come together and work really well together. Despite the enormous amount of pressure, we were having to deliver things that would normally take us months in days, and sometimes hours. MF Your team were actually among the first to see the full impact, because there wasn't so much testing going on among people who have been infected. And it was in those mortality figures that the real impact was first being revealed. SC It wasn't until our death certificate information came out, because testing was so limited in the early days, that you could kind of see the impact, and see how quickly it was increasing. MF How do we gather those numbers? SC So when somebody dies, the informant - or family member usually - will register the death, usually within five days, but depending on if it needs to go to a coroner, it could take months or even years to register that death. And we don't know about a death until it is registered. When that information gets put through all of the causes of death listed on the death certificate comes through to us at the same time with an assigned underlying cause of death, as well as contributory cause of death. So we have all of that information on each and every death registered in England and Wales. MF And it's very important to understand you can have more than one cause of death because this is very relevant to understanding how many people might actually have died because of COVID. SC The majority of deaths, regardless of cause, have more than one cause listed on the death certificate because you have complications, and one cause could lead to another cause. So the way we categorise it is deaths ‘due to’ COVID - where COVID was the underlying cause of death or any other condition - and then deaths ‘involving’ it - so where it was mentioned on the death certificate as the underlying cause or a contributory factor. MF Do you think a lot of people were actually confused by that? SC One of the things that people struggled to understand sometimes during the pandemic was that this is a different number to the public health measure. So somebody could test positive for COVID-19 but not have COVID-19 on the death certificate, because it didn't contribute to the death. So the example that gets told quite a lot is if somebody tests positive and then gets hit by a bus, it's very unlikely that COVID will be mentioned on the death certificate. MF And that's absolutely vital in understanding how many people have died ‘from’ COVID as opposed to a death ‘involving’ COVID. SC Yeah, so it's very important. The public health measure’s great because it's really fast, and it gives us a more instant knowledge of what's happening. Our statistics come out about 11 days later, but it's where COVID contributed to the death, and not just was present time of death MF That helps us to really understand what the mortality impact of COVID-19 has been so far. SC It is really important. So from the start of the pandemic to the week ending 13th of May, we know there's about 195,000 death certificates that had COVID on them, and that's the whole UK as we've worked with colleagues in Northern Ireland and Scotland to bring a UK figure together, as usually we only report on England and Wales. And then that enabled us to do further investigations about who was most at risk of dying from COVID. And we did a lot by age, place of death and any breakdowns we thought possible to try and help identify those most at risk. MF Another great strength you might say of the ONS numbers is the comprehensive nature of the way the information is gathered centrally and reported very quickly. And that was evident during the pandemic when you saw the UK numbers coming along and influencing policy decisions really quite rapidly, compared to similar countries around the world. Central to that is the whole concept of ‘excess deaths’. That's a good objective measure of impact, regardless of what doctors have written on the death certificate. Sarah, tell us how that works, particularly what is its statistical value, and what's it been saying? SC We use ‘excess deaths’, which is the number of deaths we see in a period compared to what we would expect - and to get the expected number we use an average of the previous five years. By doing this, it takes into account the direct and indirect impact of COVID, so we have a fuller measure. It's really useful as well for international comparisons, because we're not relying on everybody recording deaths in the same way. It's just a straightforward “how many deaths above what we would expect are we seeing?” MF And what has it shown so far - what has been the impact on excess deaths? SC So we've seen quite a high number of excess deaths during the pandemic. In 2020, we saw over 75,000 more deaths than we were expecting originally. In 2021 that is lower - we saw around 54,000 deaths more than we'd expect. And currently to date for 2022 we are seeing the number of deaths slightly below what we'd expect looking at our five year average. MF Do we know yet - at the least the early indications - for what this might all mean for life expectancy? SC We have released some life expectancy statistics for 2018 to 2020 as we do three-year combined, and we do see a bit of a dip in the last year because of the high number of deaths in 2020, which was due to the pandemic. We're still seeing the numbers are significantly higher than at the start of our time period, which was 2001 to 2003. Somebody in England in 2018 to 2020 would live to about 79 years as a male, or 83 years as a female. Whereas in 2001 to 2003 it was more like 76 years old for males and 81 years old for females. MF So in recent history we've seen these really quite pronounced increases in life expectancy for men and women. SC People are living longer. It’s increased more for males than it has for females. It's reducing that inequality gap, because we do see that women do tend to live longer. MF Do we know why men are catching up with women in terms of life expectancy? Is it lifestyle, nature of work perhaps? SC There is a lot more of a decline in heart diseases, and especially in males, so I think that could indicate healthier choices, which would then increase somebody's life expectancy. MF Another important concept when understanding how the ONS looks at mortalities is the whole question of ‘avoidable deaths’. So how does that work and what is it been telling us? SC So ‘avoidable mortality’ is defined as a cause of death that is either preventable - so for example COVID and appendicitis is included in this – or are treatable - so this would be different types of cancer. For those aged under 75 in 2020, 22.8% of all deaths in Great Britain were considered avoidable. This is around 153,000 deaths out of 672,000. The categories where we've seen the biggest increase since the start of our time series was alcohol and drug related disorders, which is the only group of causes where the mortality rate is significantly higher in 2020 when compared to 2001. But the biggest driver of avoidable mortality would be the cancers. MF So those figures for avoidable death might suggest then that there is still considerable disparity in life expectancy between different groups. SC So we see through our data that those living in the most deprived areas have a substantially higher rate of death from avoidable causes - with deaths due to COVID-19, drugs and alcohol being notably higher in the most deprived areas. Avoidable deaths accounted for 40% of all male deaths in the most deprived areas of England, compared to 18% in the least deprived areas in 2020. And then we see the difference again for females. It was 27% of deaths in 2020 in the most deprived areas, and then 12% in the least deprived areas. So this gap in avoidable mortality between the most and least deprived areas - it's actually at its highest level since 2004 for males, and since the data began in 2001 for females. MF James what are the factors that are driving those disparities which are, on the face of it, pretty serious? JT The difference between the most and least deprived areas is one of the most striking statistics we produce actually. And I think it really shows the importance of looking beyond those top level figures. And that's the ability we have here to look at the minute detail of the data. I mean, there's all sorts of factors that can go into life expectancy. So there are things like access to health care, nutritional aspects - there's plenty of things that can drive that gap, but it's really, really striking and definitely needs looking into. MF What's the direction of our work in this area? Because for some areas are we not seeing actually a sustained reversal of life expectancy, not just shorter life expectancy, but one that's actually getting shorter. JT I think you mentioned earlier Miles about how this mortality data had kind of risen from obscurity I think. During the COVID pandemic the spotlight has been shone on deaths and Coronavirus itself, but really there's going to be a period where we're really going to have to make best use of that data to look at the indirect effects of Coronavirus as well. So, take for example just within the pandemic we saw a big increase in alcohol related deaths in 2020, and that tallies with other research that shows that patterns of drinking have changed during that time with heavy drinkers drinking more. So beyond the pandemic as well - we're looking at things like delays to treatment times for certain diseases. So there’s plenty of analysis still to do on the impacts of the pandemic. MF Deep in the recesses of the ONS data though, the causes of deaths that are recorded - some of them are, you have to say, they're unusual, they're quite remarkable. Sarah, can you give me some examples of some of the most unusual deaths that have been recorded? SC So I’ve got a few of the least common causes of death, and I don't want to scare anyone - the numbers that I've got here are over an eight year period, so they're very rare. So I don't know if you want to see if you can take a guess at how many people are ‘bitten or stung by non venomous insects and other non venomous arthropods’? MF People attacked by bees and wasps, that kind of thing. SC Not because they're venomous, but because of the incident themselves. MF Well I'd like to think there was a very small number. I don't know - over an eight year period - hopefully less than 50 or so? SC It was less than 50. It was 12 - which is more than I was expected. Another one we have is ‘fall involving ice skates, skis, roller skates, or skateboards’? MF Can be very dangerous. I don't know, 5? SC Three! Very good guess. I for some reason thought it would be more than being bitten or stung by an insect. We've got ‘victim of lightning’? MF Rare again. Highly unusual. I don't know... 10? SC Seven! You're quite good at the guesses. I’m very impressed. MF You know, you hang around the ONS long enough and you start to get a feel for these things. What do we think is the most unusual cause of death that we've recorded? SC We've got a lot that only have one death. One of the ones that springs to mind is ‘bitten by rat’. I did expect more people to die from that than some of the other ones we've got, like ‘contact with powered lawnmower’. But I guess that's quite a dangerous thing to do, especially if you're like me and start doing it in your flip flops. So yeah, dangerous. MF Definitely not recommended.

So we've looked at births and we've looked at deaths. But what's the balance between the two at the moment, James, and what's the impact on our population of all this overall? JT Population change is driven by the number of live births and the number of deaths and the balance between those, but also the migration that takes place each year. So the difference between the number of births and the number of deaths is a component known as ‘natural change’. Over the last decade or so, although we've generally seen more births than deaths, we've actually seen a narrowing of the gap. So all else being equal, that means that the population growth will slow. Also, we did actually see a blip in 2020 when for the first time for a while the deaths exceeded births, but that's going to be due to the very high number of deaths that we sadly had from Coronavirus in that year. MF And that was highly unusual - the first time in many years we've seen that. JT Yes, that's right. So the general trend has been more births than deaths and we've seen a return to that in 2021. MF Well, there we are, proof that the ONS really does cover us from the cradle to the grave.

‘Statistically Speaking’ comes to you from the Office for National Statistics. I’m Miles Fletcher, thank you very much for listening. Join us for the next episode, which you can hear by subscribing to this podcast on Spotify, Apple podcasts and all the other major podcast platforms.

Our producers at the ONS are Julia Short, and Steve Milne. ENDS