Chart: The Aussie's valley of death
John Phillips | Digital Editor | CNBC. There is no question that the Aussie strength is a direct consequence of weakness in the U.S. dollar, Daryl Guppy writes. · CNBC

It's been relentlessly talked down by Reserve Bank of Australia Governor Glenn Stevens. It's been smashed by a sustained run of low commodity prices. And, with perverse glee, it's fall has been hailed as a sign of success even it's a prime marker of a collapsing economy.

The Aussie did its best to cling onto the narrow shelf of support near $0.78 but once that failed it has been a rapid plunge into the valley of death. This is great news for those who have traded short but it begs the question: How much longer they should stay short? The weekly chart provides some (un)pleasant answers.

The chart has two dominant features. The first is the prolonged, steady downtrend that is well defined using a Guppy Multiple Moving Average (GMMA) indicator. The fall below $0.93 in September 2014 was an accelerated continuation of the downtrend. The long-term GMMA group of averages rapidly expanded showing sustained, consistent selling pressure.

No subsequent rally has been able to cause any compression in the long-term GMMA and this confirms the grip of the bears.

The second feature is the way the Aussie trades in trading bands around $0.08 wide. These bands are used to set the downside targets in the trend.

During the prolonged downtrend the Aussie has moved between broad trading bands. These bands have matched historical support and resistance levels. The fall below $0.94 had a historical support level at $0.865. This support was broken in November 2014 and the Aussie quickly fell to $0.79.

The same trading band measurement is used to set the target below support near $0.79. This gives a downside target of $0.715, which has now been achieved and exceeded. The last time this level was achieved the Australian index was trading at 3500. That's a 37 percent fall from recent levels near 5580.

Read More Is the Lucky Country's luck finally running out?

The last time the Aussie was at $0.64 was in 2008 at the depth of the market collapse, when the ASX 200 was at 3300. That's 34 percent below current levels and 40 percent below the market peak at 5580.

This currency collapse also signals a short trade in the Australian index.

Once the target is achieved, it's followed by a period of consolidation. We use the ANTSSYS method to trade both the sustained falls below the support levels and the shorter-term consolidation volatility.

Stevens is jawboning the Aussie down to $0.67 but the chart support is at $0.64. The idea that a low dollar equals an economy in deep distress does not seem to worry the RBA, which has wound back a decade of miscalculated GDP growth figures to well under 3 percent.