condition mean min max ZT0-3 5.751105 5.751105 5.751105 ZT4-7 5.6454699999999995 5.6454699999999995 5.6454699999999995 ZT8-11 4.06211 4.06211 4.06211 ZT12-15 3.10328 3.10328 3.10328 ZT16-19 4.477555 4.477555 4.477555 ZT20-23 5.199195 5.199195 5.199195