condition mean min max ZT0-3 1737.174956 1737.174956 1737.174956 ZT4-7 1891.2815025 1891.2815025 1891.2815025 ZT8-11 1653.585023 1653.585023 1653.585023 ZT12-15 1515.876969 1515.876969 1515.876969 ZT16-19 1609.5468815 1609.5468815 1609.5468815 ZT20-23 2094.993526 2094.993526 2094.993526