Are you serious about that formula? If so, what is the link? The actual crash was about 7% in 20 minutes as the market was already down hundreds of points on the day. So, roughly half that or more in an hour to the downside would still be considered significant.
Markets are engineered and managed by the exchange by way of circuit breakers to gradually go down. Just like intraday swings without these artificial controls an oversold market would violently drop. With these circuit breakers in place the markets will halt and at least give big money an opportunity to protect their positions. These intervening actions in a sense manipulate the free market. From the 90's on the general deep pocket hedge fund strategy was holding long and scalping short. Markets tend to want to retrace 50% over the long haul. Our Government regulators through rule changes have engineered a financial market that can not withstand even a 33% retracement. Given banks can now freely trade derivatives with 30x1 leverage using savings deposits and their losses are insured by the FDIC. The previously carefully engineered long trending market has changed and created its own nemesis. Banks are no longer interested or focused in the lending biz.. they have the full faith and force of our treasury to martingale shorts to zero. They can not lose... their margin call is a bail out. If you had the ability to average down with unlimited bank, no risk and no limits why would you do anything else?
Tanked ~1.3% in less than an hour near the end, which I thought mifght be the start of a crash. But, profit taking prevailed. Still 2 more days to see if we get 3% in less than an hour.
For anybody, who googled Shroner-Rugdolf and couldn't find anything, here is the link: http://www.youtube.com/watch?v=YwxfoUt0SLE
So far, only ~1.4% in an hour time span. Profit taking took over again. I'm partially to blame as I took some profit off the table too...