condition mean min max ZT0-3 0.867403 0.6508855 1.0082775 ZT4-7 0.4349005 0.4349005 0.4349005 ZT8-11 0.8960325 0.8960325 0.8960325 ZT12-15 0.36986225000000006 0.279874 0.45985050000000005 ZT16-19 0.850324 0.850324 0.850324 ZT20-23 0.809247 0.809247 0.809247