condition mean min max ZT0-3 39.334025 32.25815 46.40989999999999 ZT4-7 42.32965 42.32965 42.32965 ZT8-11 29.2817 29.2817 29.2817 ZT12-15 0 0 0 ZT16-19 49.9923 49.9923 49.9923 ZT20-23 39.9952 39.9952 39.9952