There are two ways of looking at the NYSE short interest, which as of September 15 surged by 1.4 billion to 18.4 billion shares or just shy of the level hit on July 31, 2008:
Either a central bank intervenes, or a massive forced buying event occurs, and unleashes the mother of all short squeezes, sending the S&P500 to new all time highs, or
Just as the record short interest in July 2008 correctly predicted the biggest financial crisis in history and all those shorts covered at a huge profit, so another historic market collapse is just around the corner.
The correct answer will be revealed in the coming weeks or months.
Source: NYSE