The aggregate size of the BRICS economies is dominated by the size of China, and its growth rate. It has recently been reported that China grew by a real 6 percent in the fourth quarter of 2019, and an annual rate of 6.1 percent the year, its lowest for nearly 30 years. However, in terms of size and given the recovery of the renminbi in late 2019, this translates into something in the vicinity of $15 trillion.

The Chinese economy, at the start of this decade, is comfortably more than twice the size of the other BRICS countries put together. The next largest, India, is close to one-fifth the size of China. If China, for example, were to slow to 5.5 percent in 2021, in order for that to not have a negative impact on the BRICS aggregate performance, India would have to accelerate by 2.5 percent more than its 2020 performance.

What is also important to consider is that despite China growing at its slowest rate for nearly 30 years as the last decade ended, for the decade as a whole, it is the only one of the five that has grown in line with its growth rate potential. Three of the five, Brazil, Russia and South Africa, have all experienced a pretty miserable decade, barely growing in positive terms, and in fact, due to the fall in their currencies, they have seen their share of global GDP decline, and with it, their influence on the BRICS average.

In spite of the disappointment of Brazil and Russia in the past decade, India was not that far behind its potential growth performance, and as I will discuss more, because of its favorable demographics, it is likely to have easily the strongest real GDP growth rate of all five in the decade to 2029. I continue to wonder why South Africa was added, as economically, it not only remains tiny relative to the others, but its actual growth performance has been a persistent disappointment since it became the fifth member of the political club.

Notwithstanding all these caveats, due to the very strong performance of all the BRIC countries during 2000 to 2009, and the continued strong growth of China and India during 2010 to 2019, their combined influence on the world since 2000 has been immense. I would calculate that global GDP growth averaged around 3.5 percent in the decades 2000 to 2009 and 2010 to 2019, higher than 3.3 percent in the previous two decades. This is virtually entirely due to the influence of China and India respectively, especially China. China alone, despite its absolute rate of growth being weaker in the decade just finished, contributed more than 40 percent of all global GDP that occurred this decade.

Turning to this next decade, surely all of Brazil, Russia and South Africa must perform better than in the decade just finished? I would not be completely convinced that this is the case for either Russia or South Africa, as they are beset with persistent challenges such as their overreliance on their commodity industries, their lack of reform, and significant challenges from their labor force dynamics.

This is particularly true of the Russian economy, and unless it adopts more serious reforms, Russia will start the 2030's closer to the bottom of the next 10 economies outside the top 10, rather than just outside, where it sits today.

Brazil may grow closer to its potential, around 3.5 percent this decade, but it needs to maintain the recent progress on reforms that it started with pensions, and expand these reform efforts further, in order to allow greater space for the private sector so it is not crowded out by the inefficient government sector. They also need to reduce the dominance of commodity companies.

India could be the most exciting of the five, as unlike all the others, it has a rapidly growing labor force, and if India introduced significant reforms, including boosting its trade and investment relationship with China, it could in principle grow by more than 8 percent, perhaps some years above 10 percent. But there are not huge signs that the necessary reforms are forthcoming, indeed, on the contrary, and I think something closer to 6 percent is more likely. (It is still easily enough for India to clearly emerge as the world's fifth-largest economy).

China is likely to grow in the vicinity of 5 percent for the decade, primarily because of its ageing population and its declining labor force. It is not impossible that China could offset this demographic challenge with its own rapid productivity reforms, and with stronger success with some of its overseas trade and investment initiatives. But it will not be easy, not least because as it continues to get larger, US policymakers are likely to remain paranoid about losing their mantle of being the largest economy in the world. Indeed, there is a decent chance that even with 5 percent real GDP growth, likely more than double that of the United States, it is going to be very close by 2030, and much will depend on the performance of the renminbi.

What remains in little doubt, though, is because of China and India, and despite the other three, the global economic share and influence of the BRICS this decade will rise further.

The author is chair of Chatham House.

The author contributed this article to China Watch exclusively. The views expressed do not necessarily reflect those of China Watch.

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