RE: Global finance markets declining (August 2015)
Attempting to predict financial markets and make money on them on a short-term basis is pretty hard - just ask the legions of guys who get paid to do so with other people's money in the Wall Streets of the world (hint: they still sometimes fail and sometimes eat the consequences [can't say always with the taxpayer bailouts a few years ago]).
If I recall correctly, there's a short-term trader data sheet on this forum, and it says (again if I recall correctly) that even the best short-term traders can't quite tell you how they do it. For them, it's more of an art than a science. And like any art, it's one that took them time and experience to develop.
On a long-term basis, unless you don't adjust - which includes spending the same even when the cost of living changes - you should be fine. As I mention in my relocation thread, just as there's no 100% fool-proof online business, there's no 100% fool-proof "living off interest" plan. In both cases, you've got to balance a plan with flexibility.