condition mean min max ZT0-3 14.484215 14.484215 14.484215 ZT4-7 11.049497500000001 11.049497500000001 11.049497500000001 ZT8-11 10.738211 10.738211 10.738211 ZT12-15 11.268317499999998 11.268317499999998 11.268317499999998 ZT16-19 11.755735 11.755735 11.755735 ZT20-23 11.903488 11.903488 11.903488