protected function calcRelativeValues()
    {
        foreach ($this->stackLog as $key => $value) {
            foreach ($this->metrics as $metric) {
                foreach (array('own', 'sub', 'total') as $column) {
                    if (!isset($this->stackLog[$key][$metric . '_' . $column])) {
                        continue;
                    }
                    $this->stackLog[$key][$metric . '_rel_' . $column] = $this->stackLog[$key][$metric . '_' . $column] / $this->stackLog['timetracker_0'][$metric . '_total'];
                }
                $this->stackLog[$key][$metric . '_rel_offset'] = $this->stackLog[$key][$metric . '_start_relative'] / $this->stackLog['timetracker_0'][$metric . '_total'];
            }
        }
    }