condition mean min max ZT0-3 16.677275 15.78715 17.5674 ZT4-7 22.3277 22.3277 22.3277 ZT8-11 41.262249999999995 41.262249999999995 41.262249999999995 ZT12-15 0 0 0 ZT16-19 33.142399999999995 33.142399999999995 33.142399999999995 ZT20-23 26.8472 26.8472 26.8472