protected function loadStatsArray() {
        if (!is_array($this->stats)) {
            $stats = $this->instance->loadStatus($this->cacheKeyPrefix, $this->cacheKeySuffix);
            if (!empty($stats)) {
                $this->stats = unserialize($stats);
            }

            // make sure unserialize and load were successfull and we have array
            if (!is_array($this->stats)) {
                $this->stats = array();
            }
        }
    }