condition mean min max ZT0-3 293.580633 293.580633 293.580633 ZT4-7 340.87796000000003 340.87796000000003 340.87796000000003 ZT8-11 245.87890499999997 245.87890499999997 245.87890499999997 ZT12-15 263.202567 263.202567 263.202567 ZT16-19 274.305556 274.305556 274.305556 ZT20-23 294.8706965 294.8706965 294.8706965