condition mean min max ZT0-3 21.367849999999997 21.367849999999997 21.367849999999997 ZT4-7 16.7485 16.7485 16.7485 ZT8-11 21.236649999999997 21.236649999999997 21.236649999999997 ZT12-15 19.77395 19.77395 19.77395 ZT16-19 22.96085 22.96085 22.96085 ZT20-23 15.25835 15.25835 15.25835