I have done some charting on how Santos has historically...

I have done some charting on how Santos has historically performed versus the oil price.

Going back to 2008 you can see that Santos had 4 major falls including the current one.They range from 28% to 48% in magnitude with the GFC suffering the worst fall. Current decline is 38%. The falls lasted between 2 to 6 months and almost in all instances formed a V shaped recovery from the bottom. The recovery phases typically lasted twice as long and in two instances recovered more than the losses.
  
The second chart overlays oil (black) with Santos. Correlation is positive and strong.

Back in 2008, oil was US$40 or A$62/bbl, Santos hit a low of $9.63 (note this was the lowest point).
Now in 2014, oil is US$65 or A$77/bbl, Santos is trading at $9.40. On the basis of how many Santos shares are needed to buy one barrel of oil you are looking at a difference of negative 20% to the lowest point ever recorded during the GFC. On this basis the market must be factoring a much worse oil price assuming the exchange rate stays the same.

I know this is a simplistic illustration but provides a perspective on how much fear is instilled in the current stock price.