code: protected function compileYearlyMenu()
  	{
  		$arrData = array();
  		$arrAllEvents = $this->getAllEvents($this->cal_calendar, 0, 2145913200);
  
  		foreach ($arrAllEvents as $intDay=>$arrDay)
  		{
  			foreach ($arrDay as $arrEvents)
  			{
  				$arrData[substr($intDay, 0, 4)] += \count($arrEvents);
  			}
  		}
  
  		// Sort data
  		($this->cal_order == 'ascending') ? ksort($arrData) : krsort($arrData);
  
  		$arrItems = array();
  		$count = 0;
  		$limit = \count($arrData);
  
  		// Prepare navigation
  		foreach ($arrData as $intYear=>$intCount)
  		{
  			$intDate = $intYear;
  			$quantity = sprintf((($intCount < 2) ? $GLOBALS['TL_LANG']['MSC']['entry'] : $GLOBALS['TL_LANG']['MSC']['entries']), $intCount);
  
  			$arrItems[$intYear]['date'] = $intDate;
  			$arrItems[$intYear]['link'] = $intYear;
  			$arrItems[$intYear]['href'] = $this->strLink . '?year=' . $intDate;
  			$arrItems[$intYear]['title'] = StringUtil::specialchars($intYear . ' (' . $quantity . ')');
  			$arrItems[$intYear]['class'] = trim(((++$count == 1) ? 'first ' : '') . (($count == $limit) ? 'last' : ''));
  			$arrItems[$intYear]['isActive'] = (Input::get('year') == $intDate);
  			$arrItems[$intYear]['quantity'] = $quantity;
  		}
  
  		$this->Template->yearly = true;
  		$this->Template->items = $arrItems;
  		$this->Template->showQuantity = ($this->cal_showQuantity != '') ? true : false;
  	}
docs: Generate the yearly menu