condition mean min max ZT0-3 61.933775 23.0873 100.78025 ZT4-7 518.347 518.347 518.347 ZT8-11 31.6661 31.6661 31.6661 ZT12-15 0 0 0 ZT16-19 14.730835 14.730835 14.730835 ZT20-23 136.9725 136.9725 136.9725