condition mean min max ZT0-3 7.753335 7.09406 8.41261 ZT4-7 21.59585 21.59585 21.59585 ZT8-11 50.6708 50.6708 50.6708 ZT12-15 0 0 0 ZT16-19 32.0233 32.0233 32.0233 ZT20-23 17.42485 17.42485 17.42485