Trading
The order book
Resting bids and asks for PT and YT at each price level, with the fixed return that level implies.
Each row shows the size available and the real top-of-book quote from the underlying market. Precision controls group levels at 0.01%, 0.05% or 0.1% of return.
Why it reads in return, not price#
Two PT levels a few cents apart are almost impossible to compare at a glance. 3.41% against 3.38% is not. Reading the book in return terms makes the decision the book is actually asking you to make legible, and the same convention runs through the transaction tape, which prints the fixed return each fill implied at the moment it happened.
The tape#
Market transactions stream beneath the book: recent buys and sells across both sides, with value, notional and time. The same tape backs the My orders and My trade history tabs once you have traded in this market.