condition mean min max ZT0-3 15.020034 15.020034 15.020034 ZT4-7 15.685766000000001 15.685766000000001 15.685766000000001 ZT8-11 15.4690945 15.4690945 15.4690945 ZT12-15 14.51106 14.51106 14.51106 ZT16-19 15.154401499999999 15.154401499999999 15.154401499999999 ZT20-23 15.969815 15.969815 15.969815