For FX Swap, this is used to express the last market event for the differential between the far leg’s bid/offer and the near leg’s bid/offer in a fill or partial fill. Value can be negative. Expressed in decimal form. For example, 61.99 points is expressed and sent as 0.006199

Added in protocol FIX.4.4 (EP 21)

See in: FIX.5.0, FIX.5.0SP1, FIX.5.0SP2 EP240.