I presume you mean that these investors would be sitting on a 200% increase in their equity. To be consistent you should also consider the affect of leverage on the 6% drop in value.
By way of example:-
Assuming a buyer of a $500,000 home a few years ago with 10% equity and a 200% equity increase may be sitting on a paper profit of say $100k (prior to the recent drop). i.e. the equity has increased from $50,000 to $150,000
A 6% drop in the value of the property (from the high point of $600k) would be a paper loss of 72% (not 6% as stated in your post)
