I'm sorry, I didn't catch your name http://marketingdigitalciaocr.com/stmap_18posfo.html depo-medrol injection for allergic reaction  Assume BATS updates AAPL bid price from $530 to $531, and the ask price remains at $532. This changes the mid-price from $531 to $531.5. In the first 1.5 milliseconds, slower traders are not aware of the price change. If some such regular traders have placed an order to trade at mid-price in a dark pool, then a faster trader can buy the stock at $531 in dark pool when the synthetic NBBO gets updated. After 1.5 milliseconds, the trader can sell it for $531.5 in the dark pool. In this case the trade gains 50% of the price dislocation. Dark pools represent roughly 11% of trading volume, corresponding to 1,888,478 share of AAPL on May 9. If half of the average dislocation of 0.034 cents is captured on this volume then the fast trader would make a profit of $376,900 in a single stock on a single day. While Apple is one of the highest-volume stocks and this almost certainly represents an upper bound on the profits of strategies based on latency, the dollar figure illustrates the possible magnitude of profits and costs stemming from latency for traders continuously in the market.