condition mean min max ZT0-3 4.4937716666666665 3.30394 5.188665 ZT4-7 2.993735 2.993735 2.993735 ZT8-11 1.486971 1.486971 1.486971 ZT12-15 3.4792125 3.37588 3.582545 ZT16-19 4.279405 4.279405 4.279405 ZT20-23 5.0142299999999995 5.0142299999999995 5.0142299999999995