condition mean min max ZT0-3 55.182575 53.29495 57.0702 ZT4-7 36.29255 36.29255 36.29255 ZT8-11 37.820899999999995 37.820899999999995 37.820899999999995 ZT12-15 0 0 0 ZT16-19 52.1494 52.1494 52.1494 ZT20-23 48.598 48.598 48.598