condition mean min max ZT0-3 439.527839 439.527839 439.527839 ZT4-7 404.333685 404.333685 404.333685 ZT8-11 370.678125 370.678125 370.678125 ZT12-15 392.240023 392.240023 392.240023 ZT16-19 447.992363 447.992363 447.992363 ZT20-23 563.611476 563.611476 563.611476