public string OutputExpiry()
{
string str = "";
for (int i = Expiry.GetLowerBound(0); i < Expiry.GetUpperBound(0); i++)
{
str = str + Expiry[i].ToString(CultureInfo.InvariantCulture) + ", ";
}
str = str + Expiry[Expiry.GetUpperBound(0)].ToString(CultureInfo.InvariantCulture);
return(str);
}