average (‘;’ LIST )*
Description: static String _average = "${average;<list>[;<list>...]}";

- # average (';' LIST )*

      static String	_average	= "${average;<list>[;<list>...]}";

      public String _average(String args[]) throws Exception {
      	verifyCommand(args, _sum, null, 2, Integer.MAX_VALUE);

      	List<String> list = toList(args, 1, args.length);
      	if (list.isEmpty())
      		throw new IllegalArgumentException("No members in list to calculate average");

      	double d = 0;

      	for (String s : list) {
      		double v = Double.parseDouble(s);
      		d += v;
      	}
      	return toString(d / list.size());
      }