public function limits()
    {
        $GlobalMin = ABSOLUTE_MAX;
        $GlobalMax = ABSOLUTE_MIN;

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

        return [$GlobalMin, $GlobalMax];
    }