condition mean min max ZT0-3 14.612225 14.4833 14.741150000000001 ZT4-7 14.0444 14.0444 14.0444 ZT8-11 18.277549999999998 18.277549999999998 18.277549999999998 ZT12-15 0 0 0 ZT16-19 23.7822 23.7822 23.7822 ZT20-23 16.673000000000002 16.673000000000002 16.673000000000002