difficult extremely easy to blame Nintendo's downfall on one particular thing, with the recent trend being the 5% loss in the company's stock price after their 3DS games lineup at TGS or their analog stick doohickey. But Nintendo's overall loss of "80% of their value" over the last three years is far more difficult to explain.
Whether it's the credit crunch called the "Lehman Shock" in Japan or the Great Touhoku Earthquake six months ago, Nintendo has been greatly affected by forces outside of their control. Of course, looking at merely the 2011 chart summary (above), we can see that their decline started mainly after the launch of the 3DS.
Does this mean that Nintendo is dying a slow but inevitable death? No, that story is trollbait. Nintendo is still in no way in financial trouble. Shareholders are still confident that Nintendo will remain profitable, just perhaps not has profitable within the next couple of years as the days of the Wii and Nintendo DS.