It sounds like the beginning to a bad joke, right? But seriously, why is the Canadian Dollar (aka Loonie) beating the Australian Dollar (AUD) when the two currencies are placed head-to-head?

The currency markets tend to be very Dollar-Centric, in that they tend to view most currencies relative to the US Dollar (and to a lesser extent, the Euro), rather than to each other. When it comes to the Aussie and Loonie, then, traders at the moment seem content to see them as relatively strong, since both are appreciating against the Dollar. After all, the AUD/CAD pair accounts for only a small fraction of overall trading activity, which means that liquidity is lower and spreads are higher. Why bother?

But this ignores the fact that an important battle is currently being waged by the two currencies not only against the Dollar, but also against the other. It’s not as if the AUD/CAD rate is determined solely based on triangular arbitrage (i.e. indirectly from the AUD/USD and USD/CAD). On the contrary, there are unique factors which determine this exchange rate irrespective of others, as well as specific financial instruments.

But enough with the palavering!Let’s try to understand the idea of parity as it exists between the Loonie and Aussie, and not relative to the Greenback. I like to begin any analysis by looking at a chart. But as with any financial chart, a different time period changes the whole picture. In this case, the 1-year chart shows the Australian Dollar gaining in 2009 (in fact it was the highest performer last year among all of the majors) from the lows of the credit crunch, but retreating in 2010 away from parity. It is this latter trend that I want to elucidate here.

On paper, the Aussie would seem to be the clear favorite. As a result of this month’s interest rate hike by the RBA, the benchmark Australian rate (4%) is now a healthy 3.5% higher than its Canadian counterpart (.5%). This should favor the Aussie among carry traders looking for the highest yield differentials. In addition, the Australian Dollar accounts for a higher portion (6.7% versus 4.2%) of forex turnover than the Canadian Dollar, according to the most recent data, which means that the AUD wins the liquidity battle as well. Meanwhile, Australia’s public debt is near the low end among developed countries, at almost 15% of GDP. After a record 2009 budget deficit, Canada’s public debt is close to 80% of GDP and is among the highest the world. Finally, Australia’s economy was one of the first to emerge from recession (some say it never even officially entered recession), certainly before Canada.

But all of this is in the past. “Canada is on course to be the first Group of Seven nation to erase its budget gap after the global financial crisis.” [Australia should have won this distinction, but alas, it’s not a member of the G7]. In 2009 Q4 (the most recent for which data is available), Canada’s economy grew at 5%, compared to 2.7% in Australia. While the US economy – Canada’s largest trade partner – is accelerating, China – Australia’s most important trade partner – is attempting to slow down.

While both the Aussie and Loonie are thought of as commodity currencies, the Loonie is currently benefiting from higher oil prices while the Aussie could suffer from peaking coal and iron ore prices. Volatility (as implied by options contracts) is lower for the Loonie, and this is just as significant as the interest rate differential, when it comes to the carry trade. When you consider finally that “Canada’s financial system was named the soundest in the world for two consecutive years by the Geneva-based World Economic Forum,” its banks are all financially sound, and the attention garnered by the Vancouver Olympics, it’s no wonder that the Loonie is now edging ahead.

Over the last five years, the two currencies have been pretty stable against each other. [Against a basket of other currencies, the Loonie is ahead, with a 20% total appreciation compared to the Aussie’s 17% rise]. Thus, the current ebb could be a necessary correction. While analysts like to see things in terms of important psychological milestones, there’s no real reason why the two currencies should trade at 1:1 (parity), and the equilibrium value could very well be below the current level.

This is evidently how the markets feel, as the Aussie just slipped below its 200-day moving average against the Loonie for the first time since 2008. In addition, “Investors paid the largest premium in almost a year last month for Australian dollar put options versus the Loonie. The premium of contracts granting the right to sell the Aussie versus the Canadian currency in one week over those for buying increased on February 8 to 1.18 percentage points, the biggest since April 2009.” After all, the Aussie’s appreciation in 2009 was the highest in 15 years. Perhaps it’s only natural that all else being equal, it should fall a bit in 2010.