How we work
We want to offer views and insights that go further than others. That comes with a responsibility to use the best methods and sources. So this is about those sources and methods, including our engagement with you and a standing invitation to challenge.
Our approach
We are seeking to understand and share understanding of our world. Of course, it’s complex, ‘organised on several different temporal scales from the unchanging to the fleeting occurrence’ (Braudel). We don’t want to just tell you about it, or comment on today’s news. We don’t ever want to be derivative, shallow or clutchers of pearls. We are looking deeper, at the forces of demographic retreat, rampant digitisation, and the resulting challenges to ideas of democratic legitimacy. There are others too – climatic and microbial challenges, issues around religion, radicalisation and migration, for example. But we see the demographic and digital tides as big, under-appreciated and essential. That’s usually our starting point.
Demography & Population measures
We are not demographers, nor politicians nor technologists. We look at the impact of demography, just as we do democracy and data. So we need to be clear about the numbers and measurements we use.
Total Fertility Rate (TFR) is a snapshot - how many births would there be if this year’s pattern of birth were repeated across the entire cohort of women. It’s a handy if somewhat misleadingly-titled guide and more importantly is often the headline rate. We’ve used it a lot.
Completed Fertility Rate (CFR) is, in current demographic circumstances, a couple of points higher because it measures how many children women have actually had by the time they pass beyond regular fertility at between 45 and 50. So it includes delayed births too. Such delays suppress TFR - known as the “tempo effect”. The drawback is that it measures the past.
But it’s critical to note that , at current rates of fertility, the tempo effect causes the TFR to slightly underestimate the actual fertility rate (it would overestimate if the world were experiencing a baby boom). It doesn’t change the basic conclusions but it does partly explain why with such dramatic falls in fertility the world doesn’t yet feel depopulated and indeed that we haven’t yet reached peak human.
Demographers also look at the GRR (Gross Reproduction Rate), NRR (Net Reproduction Rate), and population level ratios, critically between children and women of reproductive age (to understand and manage, analytically, the impact of longevity on absolute human numbers but not on fertility). As a final confusion, different languages define ‘fecundity’ and ‘fertility’ differently. We can safely leave this to the experts.
In our reporting, unless we say otherwise, the figures we use are TFR, qualified by the above rider.
Perivista’s data sources and methods
Perivista deals with a wide range of sources. We are of course responsible for the conclusions we draw from them. But the integrity and relevance of any source can and should be questioned. Even statistics that tell the truth rarely tell the whole truth.
Our first call is on government and other official data sources. Clearly they all operate to different standards of integrity, availability, and reliability, and in their own distinct circumstances. So for example the Russian statistics office seems to be publishing less data broken down by area, possibly (though there’s no acknowledgement ) so that the demographic consequences and inequalities of the ‘Special Military Operation’ can remain opaque. More insidiously, the UN figures on live births by nation, which appear at the end of the year, are not outturns but projections taking trends and events into account. So they must be approached with caution.
Once we have a picture from the official accounts, we use other open sources to discover whether there is an analytical hinterland behind them. So for example we might look at school records to verify or otherwise the number of individuals in an age cohort.
We then look at external data sources. This is especially important when considering the impact of data-driven behavioural change. We include insights from subject-matter experts where we can, and especially where we are looking at new insights.
We then subject all the metrics to an internal red team, supported by a proprietary system which brings soft, hard and wetware all to bear.
Only then do figures make it to the page.
The judgments we then offer are our own. They reflect our experience and our judgement, tested against the views (we hope the critical views) of a lot of people.
Challenge & feedback
None of this is perfect. The world isn’t. And we know we are asking a lot from you, as members of this community of thought, in bandwidth. Our written work is constructed to be load bearing, and our podcasts modelled on decades of Ministerial briefing, not gentle conversation. Our task is to make sure that everyone gets out more than they put in. Our invitation: we welcome any challenge to our figures and to our analysis. If the reader’s first response is “that can’t be right”, then we’ve done our job. We don’t want to reheat and repeat others’ commentary; we want to look beyond and below conventional thinking about today’s world.
Questions, further work & suggestions for future topics
Finally, if our writing gets you thinking, great.
We’re open to questions – either general or specific.
If you want, we can provide tailored analysis and advice for you or your organisation. And we’d love to hear your ideas for future topics.
As you get to know our work, we hope you’ll see places and questions where we can add real value.
Please ask!