condition mean min max ZT0-3 0.27147099999999996 0.27147099999999996 0.27147099999999996 ZT4-7 0.3852875 0.3852875 0.3852875 ZT8-11 0.5209705 0.5209705 0.5209705 ZT12-15 0.36765349999999997 0.36765349999999997 0.36765349999999997 ZT16-19 0.549204 0.549204 0.549204 ZT20-23 0.4011436666666667 0.4011436666666667 0.4011436666666667