Example.....say the pps is 63.5 and the ask on l2 is 63.7 and bid is 63.4
If someone buys the ask it now upticks the price to the next l2 orders are filled and that sale will be in green. Any orders at that price now ill be black because the pps will now go up nor down till all the orders are filled so blacks are sideways sales up nor down. Green are uptick sales that send the pps to the next level on l2 and red are sales that down tick. Thats why you see 100 block sales to down tick the stock so people can keep loading the ask side if they want to manipulate it. So that a stock dont go blowing through the roof
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