symbolName = xmlAsciiDecode(tag, SYMBOL_NAME, XML_PASS);
exchangeExtra = xmlAsciiDecode(tag, EXCHANGE_EXTRA, XML_PASS);
final byte baseCode = xmlByteDecode(tag, FRACTION_DDF, XML_STOP);
final DDF_Fraction frac = DDF_Fraction.fromBaseCode(baseCode);
setFraction(frac);
// FIXME, MDEX ddfexchange code missing
final byte exchCode = xmlByteDecode(tag, EXCHANGE_DDF, XML_PASS);
final DDF_Exchange exch = DDF_Exchange.fromCode(exchCode);