This Condition allows you to evaluate the traded volumes on a selection as bets are matched.

Two different values can be evaluated:

• Last Traded Amount: represents the last amount traded during the previous sampling interval for the selection. The sampling interval is the time between one evaluation of the Conditions and the next, and corresponds to the market data refresh rate, whether using API NG or API Stream.
• Current Traded Amount: represents the amount being traded at the time the Condition is evaluated, i.e. during the current sampling interval.

These values can be compared with a fixed value, a Default Value, or the result of a formula.

Trade Side
You can select the side of the trade (BACK, LAY, or UNDETERMINED).
A BACK trade is generated by a Back bet, while a LAY trade is generated by a Lay bet. Since Betfair does not provide a detailed list of all individual trades, the program estimates the trade side based on the last traded odds and the current state of the order book.
The UNDETERMINED side refers to a trade that increased the selection's total traded volume but for which it was not possible to determine whether it occurred on the BACK or LAY side. This may happen because the order book changed more frequently than the market sampling rate, or because there are no remaining amounts in the order book at the traded odds that would allow the trade side to be determined.