condition mean min max ZT0-3 24.013752 24.013752 24.013752 ZT4-7 26.280851 26.280851 26.280851 ZT8-11 32.1572095 32.1572095 32.1572095 ZT12-15 27.441995499999997 27.441995499999997 27.441995499999997 ZT16-19 28.359291 28.359291 28.359291 ZT20-23 24.593117499999998 24.593117499999998 24.593117499999998