condition mean min max ZT0-3 11.12955 11.12955 11.12955 ZT4-7 8.852325 8.852325 8.852325 ZT8-11 9.73288 9.73288 9.73288 ZT12-15 8.991215 8.991215 8.991215 ZT16-19 12.3352 12.3352 12.3352 ZT20-23 10.7324 10.7324 10.7324