anchor.diff:  begin
     if (FDataType = ptFloat) then
     begin
  -    Result := ValueAsDouble;
  +    if VarIsNull(FValue) or VarIsEmpty(FValue) then
  +      Result := 0
  +    else
  +      if VarIsFMTBcd(FValue) then
  +        Result := BCDToDouble(VarToBCD(FValue))
  +      else
  +        Result := FValue;
     end
     else
     begin
  
positive.code: begin
    if (FDataType = ptTime) then
    begin
      Result := ValueAsDouble;
    end
    else
    begin
  
negative.code:   DefaultParamCheck : boolean = true;
  
  implementation
  uses
    FmtBCD;
  
  function DataTypeToParameterDataType(aValue: TFieldType): TmParameterDataType;
  begin
  