condition mean min max ZT0-3 17.21085 17.21085 17.21085 ZT4-7 17.75205 17.75205 17.75205 ZT8-11 14.24295 14.24295 14.24295 ZT12-15 14.54415 14.54415 14.54415 ZT16-19 12.2457 12.2457 12.2457 ZT20-23 14.25965 14.25965 14.25965