condition mean min max ZT0-3 25.086925 23.21725 26.9566 ZT4-7 21.80505 21.80505 21.80505 ZT8-11 24.14085 24.14085 24.14085 ZT12-15 0 0 0 ZT16-19 30.90885 30.90885 30.90885 ZT20-23 25.757550000000002 25.757550000000002 25.757550000000002