condition mean min max ZT0-3 16.101987586 7.456470938 24.747504233999997 ZT4-7 62.9438635675 50.21395291 75.673774225 ZT8-11 113.432413175 94.8235891 132.04123725 ZT12-15 67.0437904475 42.498862214999996 91.58871868 ZT16-19 21.359906135 17.49800239 25.22180988 ZT20-23 10.339566094 8.049541928 12.62959026