here is a snap from my broker of the 5min chart for brexit ref and todays drop...
you can see that one looks like intelligible decision making is being made and the other is just algo liquidity switch
**edit
sorry if the earlier pic was a bit misleading ...here is the same 900++ tick drop in red (yes i know broker pricing will differ, but this is the same broker reacting to both situations)
on the left it took ~115 mins to achieve the same movement as <1 min on the right
you can see that one looks like intelligible decision making is being made and the other is just algo liquidity switch
**edit
sorry if the earlier pic was a bit misleading ...here is the same 900++ tick drop in red (yes i know broker pricing will differ, but this is the same broker reacting to both situations)
on the left it took ~115 mins to achieve the same movement as <1 min on the right
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