I am reading the Key Assumptions on Page 41: 2014 POG US$1,300,...

I am reading the Key Assumptions on Page 41:
2014 POG US$1,300, Probable reserves 820,000, Production capacity for next 5 years 120k.
2015 POG US$1,200, Probable reserves 590,000, Production capacity for next 5 years 135-150k.
And these changes are leading to the impairment charge. To me if they mine quicker because of increased capacity that's a good thing.

Indeed on page 42 they give a sensitivity analysis of the impairment charges:

	Column 1	Column 2
0	Assumption change	Effect on Impairment of Co-O CGU $’000
1	US $100 per ounce change in gold price	54,200
2	1 percent increase/decrease in the discount rate	4,780
3	5 percent increase in operating costs	36,700