coal price

Can anyone shed some light on the price table below?

Newcastle Coal now down to 83.60 us.... Yet we are at 80c, sp was in the 50s when coal was in the 90s.... Has the world gotten used to commodities without the heated prices? After all if rev goes down companies find was to produce cheaper- the ones that don't die......

Is coal really 83.6 or is this something to do with exchange -

In June aud:us between 1.00 to 1.02', today we at 1.02..???

Coal price below from index mundi
http://www.indexmundi.com/commodities/?commodity=coal-australian

Month Price Change
Mar 2012 112.59 -
Apr 2012 108.88 -3.30 %
May 2012 101.21 -7.04 %
Jun 2012 91.73 -9.37 %
Jul 2012 94.54 3.06 %
Aug 2012 97.50 3.13 %
Sep 2012 96.43 -1.10 %
Oct 2012 83.60