New insights: Best decade ever?

Measuring success — comparing the progress of global development in relative vs. absolute terms

Laurence Chandy
27 January 2020
Letter from our Director  |  5 minute read

The end of 2019 prompted numerous reflections by columnists and commentators on the past decade. Most of these, in keeping with global sentiment, were negative. Thus, when the Swedish academic, Johan Norberg tweeted on New Year’s Eve that “the 2010s were the best decade ever”, it understandably generated a lot of attention. The tweet contains a graph illustrating the diminishing prevalence of a number of the world’s ills: extreme poverty, child mortality, hunger, illiteracy, AIDS deaths and pollution deaths. By all these measures, the world has gotten better in the past ten years, and by some, progress has been dramatic.



Johan’s tweet makes an important point by acknowledging this progress. Such progress tends to go unnoticed and underreported, because it reflects slow-moving trends and changes happening mostly in far-flung parts of the world.

While these six indicators are heading in the right direction, others aren’t. My last post focused on climate change and the relentless rise of global emissions and temperatures, and my post before that described the diverging trends in 21st century nutrition. But the point remains: there’s a lot in Johan’s tweet to cheer.

What about the claim that the 2010s were the best decade ever?

If we wanted to identify the best decade in history to be alive based on Johan’s six indicators, there’s no doubt that the 2010s win. Other than AIDS deaths, all these global ills have been on a long-term downward trajectory with people facing a lower chance of incurring them with each passing decade.

But Johan’s tweet implies something different: that the 2010s saw the greatest period of progress in a single decade.

One way to compare progress across decades is to look at how far the indicators fell relative to where they stood at the start of each decade. In Figure 1, we make this comparison between the 2010s and the preceding decade — what American English awkwardly refers to as the “aughts” and British English cheekily calls the “noughties”. The two decades appear equally matched. The 2010s saw the greatest relative progress on extreme poverty and AIDS deaths, the noughties performed better on hunger and child mortality, and there’s no daylight between the two on pollution deaths and illiteracy.

However, the above comparison masks how far the prevalence of Johan’s six indicators fell in absolute terms, which we illustrate in Figure 2. For instance, when the rate of extreme poverty nearly halved in the noughties, this brought its prevalence down approximately 12 percentage points. In the 2010s, estimates suggest that the poverty rate more than halved but from a much lower base, resulting in a smaller reduction of around 9 percentage points. Altogether, 5 of the 6 indicators saw a smaller reduction in the 2010s than the noughties.

This in no way diminishes from the real achievements of the 2010s, but it rebuts Johan’s claim that the decade was the best ever.

This result was perhaps to be expected. The noughties were characterized by rapid economic growth and improved governance across the developing world, coupled by big boosts in investment marshaled by major global initiatives and aligned around narrow development goals. These factors have proven hard to sustain or emulate in the 2010s. Moreover, as the six global ills captured in Johan’s tweet have diminished, they have also become concentrated in places where progress may be harder to achieve.

Yet this modest slowdown in progress is at odds with the ambition of the development community, who through the Sustainable Development Goals aspired to ever-faster progress, and a promise of transformation between 2015 and 2030. Hence we hear urgent calls today for a decade of action, recognizing that performance against the goals is way off-track.

This urgency is surely justified. The headline goal for 2030 — to end extreme poverty — is one area where our above analysis suggests that we are still on a strong trajectory. Yet the reality is that progress on this measure is halting too: our data just haven’t caught up to the present. The front line of extreme poverty is now Sub-Saharan Africa: home to 27 of the 28 poorest countries in the world and a rapidly increasingly share of the world’s poor. Ongoing global progress hinges overwhelmingly on Africa’s performance. However, meager economic growth combined with high population growth mean that average incomes in the region have increased by only a single percent since 2014.

In December, I had the opportunity to meet with African scholars and policymakers in Addis Ababa to discuss how the region’s progress on extreme poverty could be enhanced, at a meeting called by the UN Economic Commission for Africa. I left the meeting struck by the resolve of the attendees whose expectations seemed well attuned to the challenge the continent now faces.

As we look ahead to the 2020s, the past is prologue. Our distance from the 2030 targets is determined by the historical progress that has brought us to this point. That progress reminds us of what is possible, but provides no guarantee of ongoing success.

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