condition mean min max ZT0-3 1.78064 1.78064 1.78064 ZT4-7 1.213274 1.213274 1.213274 ZT8-11 1.996175 1.996175 1.996175 ZT12-15 1.3163 1.3163 1.3163 ZT16-19 2.013045 2.013045 2.013045 ZT20-23 1.456385 1.456385 1.456385