code: function(year) {
  			var date = this._validate(year, this.minMonth, this.minDay, $.calendars.local.invalidYear);
  			year = date.year();
  			var baktun = Math.floor(year / 400);
  			year = year % 400;
  			year += (year < 0 ? 400 : 0);
  			var katun = Math.floor(year / 20);
  			return baktun + '.' + katun + '.' + (year % 20);
  		}
docs: Format the year, if not a simple sequential number.
  @memberof MayanCalendar
  @param year {CDate|number} The date to format or the year to format.
  @return {string} The formatted year.
  @throws Error if an invalid year or a different calendar used.