condition mean min max ZT0-3 9.253451 9.253451 9.253451 ZT4-7 11.0416545 11.0416545 11.0416545 ZT8-11 9.521036 9.521036 9.521036 ZT12-15 10.4128455 10.4128455 10.4128455 ZT16-19 9.107964500000001 9.107964500000001 9.107964500000001 ZT20-23 10.452509 10.452509 10.452509