public void Update(FxRate rate)
 {
     this.Bid = rate.Bid;
     this.Offer = rate.Offer;
     this.PreviousOffer = rate.PreviousOffer;
     this.Timestamp = rate.Timestamp;
     this.Spread = getSpread(rate);
     this.Delta = getDelta(rate);
 }
        public static DisplayFxRate Create(FxRate rate)
        {
            var display = new DisplayFxRate()
                {
                    Ccy = rate.Ccy,
                    Bid = rate.Bid,
                    Offer = rate.Offer,
                    PreviousOffer = rate.PreviousOffer,
                    Timestamp = rate.Timestamp,
                    Spread = getSpread(rate),
              Delta = getDelta(rate)
                };

              return display;
        }