condition mean min max ZT0-3 0.869323 0.780206 0.943245 ZT4-7 0.453813 0.453813 0.453813 ZT8-11 0.598962 0.598962 0.598962 ZT12-15 0.7979665 0.771502 0.824431 ZT16-19 1.074615 1.074615 1.074615 ZT20-23 0.789866 0.789866 0.789866