"Nice to have you back after all those holidays!

"I have been waiting until May 7th so that the spike on May 6th 2010 will disappear from all my 1-year charts, enabling them to be shown full size:

"So to celebrate the anniversary I thought I'd read up about what actually happened on that day. It makes fascinating reading:


"It makes me wonder. Did the lucky people who bought Accenture shares for one cent get to keep them at that price? And did the people who sold Hewlett Packard for over $100,000 a share get to keep the money?

"It also makes me wonder - are we actually safe from these things yet? If not, one must NEVER put in a market order. And one should only use limit orders, never stop orders.

"There was also a big dip in e.g. the S&P after that, from which it only really recovered in September. Was this caused by the lack of trust engendered by the flash crash, or was there another reason for it? Just so I can make sense of the charts."

David Fuller's view Thanks for your comments and interesting questions. I think the 'flash crash' left us with more questions than answers, although I assumed that high-frequency trading was a factor. I thought that some of the extreme moves were not regarded as valid by US exchanges, but I am not sure about this.

I do think that the event helped to undermine investor confidence at a time when the market was due for a correction in response to an overextended rally.