condition mean min max ZT0-3 166.850086 166.850086 166.850086 ZT4-7 166.6426265 166.6426265 166.6426265 ZT8-11 160.924954 160.924954 160.924954 ZT12-15 179.9956535 179.9956535 179.9956535 ZT16-19 170.572168 170.572168 170.572168 ZT20-23 156.1084935 156.1084935 156.1084935