condition mean min max ZT0-3 14.654328 14.654328 14.654328 ZT4-7 11.4630715 11.4630715 11.4630715 ZT8-11 10.005658 10.005658 10.005658 ZT12-15 9.9674795 9.9674795 9.9674795 ZT16-19 9.4041015 9.4041015 9.4041015 ZT20-23 10.155394000000001 10.155394000000001 10.155394000000001