condition mean min max ZT0-3 134.1917728 122.45608130000001 145.9274643 ZT4-7 97.226323115 91.10559018000001 103.34705604999999 ZT8-11 57.971798237499996 47.774102135 68.16949434 ZT12-15 32.9045780725 31.279636855 34.529519289999996 ZT16-19 83.569666705 67.538142375 99.601191035 ZT20-23 114.55476205 110.97450124999999 118.13502284999998