condition mean min max ZT0-3 10.51605 10.51605 10.51605 ZT4-7 6.81582 6.81582 6.81582 ZT8-11 3.073735 3.073735 3.073735 ZT12-15 3.608295 3.608295 3.608295 ZT16-19 8.67358 8.67358 8.67358 ZT20-23 11.7926 11.7926 11.7926