condition mean min max ZT0-3 9.42109 9.42109 9.42109 ZT4-7 6.76556 6.76556 6.76556 ZT8-11 6.034395 6.034395 6.034395 ZT12-15 8.821560000000002 8.821560000000002 8.821560000000002 ZT16-19 11.858799999999999 11.858799999999999 11.858799999999999 ZT20-23 10.75045 10.75045 10.75045