There's nothing like a big round number to concentrate the mind. Investors, in particular, have a tendency to get excited about arbitrary price points with an abundance of zeroes. Think the 1999 best-seller 'Dow 36,000' (we're still waiting but not for long, I suspect).

Last week's big round number was 10,000 - the price in (US) dollars for a tonne of copper. It was the first time the metal, which is used in everything from kettles to electric vehicles and wind turbines, had fetched that price since the peak of the last industrial metals upswing in 2011.

When you consider that you could have bought a tonne of copper for US$4,300 a year ago, the recent rise is quite something. It is hardly surprising that talk of a commodities boom is picking up. And not just any old rally; what's getting investors excited is the prospect of a commodities supercycle.

Most industries are cyclical to an extent, but commodities are more so than most because the price of metals, crops and energy are closely tied to real day to day supply and demand. The price of a share can be sustained by hopes for future growth in earnings, but the cost of a tonne of copper reflects the balance of buyers and sellers today.

This means that commodities are always moving in mini bull and bear markets. Rising demand and constrained supply pushes prices higher and that, in turn, creates the oversupply that brings the market back into balance.

A supercycle is different. It is always driven by some kind of structural change in which demand is transformed over a period of many years, and usually all around the world at the same time. The mass production of motor cars in the early part of the last century, and then the growth of aviation, fundamentally changed the supply/demand dynamic for oil, for example.

Commodity supercycles are not that common, but when they kick in they last for years. There have probably only been four proper ones in the past 150 years. The first was triggered by American industrialisation and urbanisation, fuelled by the US's railway boom and accelerated by the First World War's demand for armaments.

The causes of the other three are well-known: the post-war recovery in Europe and Japan; the 1970s oil shock, boosted by Lyndon Johnson's Wars on Poverty and in Vietnam, and the space race; and China's rapid growth after it joined the World Trade Organisation in 2000.

So, the big question today is whether the recent price signals, from copper (which has doubled in a year), iron ore, nickel, zinc and other metals, indicate a temporary upswing as the world emerges from the Covid pandemic or the start of something more substantial. The answer to that question may well be one of the most important for investors today.

It's easy to make the case for a short-term bull market in commodities. The economic data around the world in recent weeks has surprised economists if not stock market investors who identified the possibility of a V-shaped recovery in activity a year ago. Coupled with short-term supply interruptions due to the pandemic, and longer-term constraints thanks to a decade of falling prices, it's no surprise that prices should have bolted in recent months.

What's more interesting, however, is the potential for that all-important multi-decade shift in demand. And for that you need look no further than the twin drivers of Joe Biden's transformational spending programme and the energy transition that has the potential to absorb however many trillions of dollars the world's big-spending governments want to print.

A third of Biden's so-called American Jobs Plan is earmarked for transport infrastructure and electric vehicles. China, too, has decided that electric vehicles will be the mainstream option within 15 years. Here in Europe, time has already been called on the internal combustion engine over the next decade or so. By 2040, Wood Mackenzie forecasts, there could be 300 million electric vehicles on the world's roads. In 2019 there were 5 million.

And that is just cars. Factor in green energy generation, let alone the once in a hundred years rebuilding of crumbling infrastructure on both sides of the Atlantic, and the demand for green metals like copper, nickel, aluminium and platinum is likely to soar. Glencore, the commodities trader and mining company, thinks demand for copper could double in 30 years.

Importantly, capital investment in new capacity is well below what is needed to meet that growth in demand. Of the more than 200 big copper deposits to have been found in the past three decades, only a handful have come in the last 10 years. Only 80 or so are now in production or have been closed. It takes years to develop a copper mine and in recent years shareholders have encouraged the payment of dividends over preparing for a future boom.

So, how might investors position themselves for the supercycle ahead? The simplest and cheapest way is via a commodities-focused exchange traded fund. There are plenty of different flavours but a broad-based exposure to metals and energy makes sense. To turbo-charge returns in the event of a prolonged upswing, investing directly in commodity producers is a better idea. With relatively fixed costs, miners' and oil companies' earnings will rise more quickly than the price of their underlying resources.

The other advantage of investing in commodity-related shares is that they can also deliver a high and sustainable dividend income. The combination of price gains and re-invested dividends over the duration of a typical supercycle might point you towards your own big round number.

By now most investors are tiring of their inboxes being filled by sell-side economists and strategists talking about reflation, how much more optimistic they are relative to consensus, and for how much longer the reflation trade will persist.

To be clear, there were very few people talking about a strong V-shaped recovery this time last year. Indeed, a scan of the forecasts of leading sell side economists in April 2020 shows consensus* forecasts of 3% for the CY21 for Australia and 3.8% for the USA.

Indeed, peak pessimism was not reached until September 2020, when economic growth downgrades ceased and modest upgrades commenced. Currently, consensus for CY21 has risen to 5.7% in the USA and 4.4% for Australia.

By contrast, our forecasts for the US in 2021 - which we published in mid-April 2020 - was 6.5% (represented by the cross in Chart 1). For Australia (Chart 2) we were even more optimistic, forecasting 7.0% economic growth. As we moved through 2020, it was clear the expected contraction in economic growth in 2020 was going to be less than expected and hence we reduced our forecast rebound in Australia's economic growth in 2021 to a still sizeable 6.0%.

Much of our more upbeat analysis was based on: (i) the nature of the shock being more akin to a natural disaster; (ii) the quantum of the fiscal packages; (iii) excess credit growth; (iv) the outlook for vaccine development; (v) and the prospect of pent up demand.

One year on, the clambering to upgrade growth estimates has only intensified. Over the past two months, consensus forecasts for Australian economic growth in 2021 have been upgraded a further 0.7%. In the USA the revision over the past 2 months is a remarkable 1.6%.

In other words, consensus economic growth forecasts are now more realistic, but the upward revisions are not yet complete and there is still scope for consensus to upgrade economic growth further in coming months to nearer our long held forecasts.

Indeed, when we compare our forecasts for economic growth to consensus there are now examples of economic growth forecasts for the US that exceed our forecast. The most notable is the Bank of Canada's recent upgrade of 2021 US economic growth from 5.0% to 7.0%. Given the US is Canada's largest trading partner, the Bank of Canada has a strong incentive to get its US outlook near the mark! The Bank of Canada also lifted its global growth forecast in 2021 to 6.8%, which is 1.25% higher than any global growth year since IMF data commenced (1980) and 0.8% above the IMF's April forecasts!

However, one of the largest gaps between consensus and our own 2021 forecasts is for Australia. We remain 1.5% above the consensus forecast and around 1% above the most optimistic forecaster. Given there remains an appreciable gap between our forecasts and other forecasters, it's reasonable to ask what supports our optimism?

1. Australia's data continues to consistently beat economic forecasters

Charts 3 and 4 show our calculation of economic data surprises for economic activity and inflation relative to consensus forecasts (US vs Australia). A positive reading represents economic data beating consensus expectations weighted by data importance and time decay. Clearly, Australia's economic activity data is not only continuing to beat increasingly upbeat economic forecasts, the positive data surprises are larger in Australia.

2. Real economic growth is expanding at pace

Secondly, our nowcasting techniques (Chart 5) for gauging in real-time how fast the economy is expanding already suggest that real economic growth is expanding at 4%yoy by the end of 1Q2021. That is, we are about to see a very solid 1Q GDP print for Australia that we expect will be the catalyst for a further upgrade of the consensus view.[1]