condition mean min max ZT0-3 676.413597 676.413597 676.413597 ZT4-7 634.8885250000001 634.8885250000001 634.8885250000001 ZT8-11 434.974288 434.974288 434.974288 ZT12-15 509.9889465 509.9889465 509.9889465 ZT16-19 442.4090845 442.4090845 442.4090845 ZT20-23 484.1008515 484.1008515 484.1008515