What goes up must come down (but not necessarily at the same rate): Testing for asymmetry in New Zealand time series

The notion that many macroeconomic variables fluctuate asymmetrically over time is not new to economic theory but it is relatively new to empirical economics. The most common empirical representations of aggregate time series are usually smooth and sluggish. This study employs the test for steepness and deepness to the cyclical component (extracted via the HP filter) of eight New Zealand economic time series. We find that there is no evidence of asymmetry in the cycles of any of the series.