public function onVisitProcessed(OutputInterface $output)
    {
        ++$this->processed;

        $percent = ceil($this->processed / $this->amountOfVisits * 100);

        if ($percent > $this->processedPercent
            && $percent % $this->percentStep === 0
        ) {
            $output->writeln(sprintf('%d%% processed. <comment>%s</comment>', $percent, $this->timer->__toString()));

            $this->processedPercent = $percent;
        }
    }