condition mean min max ZT0-3 598.693595 598.693595 598.693595 ZT4-7 585.6070804999999 585.6070804999999 585.6070804999999 ZT8-11 499.4528605 499.4528605 499.4528605 ZT12-15 536.268052 536.268052 536.268052 ZT16-19 427.63424 427.63424 427.63424 ZT20-23 470.64771599999995 470.64771599999995 470.64771599999995