public static function get_updates_count() {
		$cache_key = '_woocommerce_helper_updates_count';
		$count     = get_transient( $cache_key );
		if ( false !== $count ) {
			return $count;
		}

		// Don't fetch any new data since this function in high-frequency.
		if ( ! get_transient( '_woocommerce_helper_subscriptions' ) ) {
			return 0;
		}

		if ( ! get_transient( '_woocommerce_helper_updates' ) ) {
			return 0;
		}

		$count       = 0;
		$update_data = self::get_update_data();

		if ( empty( $update_data ) ) {
			set_transient( $cache_key, $count, 12 * HOUR_IN_SECONDS );
			return $count;
		}

		// Scan local plugins.
		foreach ( WC_Helper::get_local_woo_plugins() as $plugin ) {
			if ( empty( $update_data[ $plugin['_product_id'] ] ) ) {
				continue;
			}

			if ( version_compare( $plugin['Version'], $update_data[ $plugin['_product_id'] ]['version'], '<' ) ) {
				$count++;
			}
		}

		// Scan local themes.
		foreach ( WC_Helper::get_local_woo_themes() as $theme ) {
			if ( empty( $update_data[ $theme['_product_id'] ] ) ) {
				continue;
			}

			if ( version_compare( $theme['Version'], $update_data[ $theme['_product_id'] ]['version'], '<' ) ) {
				$count++;
			}
		}

		set_transient( $cache_key, $count, 12 * HOUR_IN_SECONDS );
		return $count;
	}