public function containsData()
    {
        if (!isset($this->Data["Series"])) {
            return false;
        }

        foreach (array_keys($this->Data["Series"]) as $Key) {
            if ($this->Data["Abscissa"] != $Key
                && $this->Data["Series"][$Key]["isDrawable"] == true
            ) {
                return true;
            }
        }

        return null;
    }