condition mean min max ZT0-3 31.74114186 30.50599452 32.9762892 ZT4-7 5.04240374675 3.332664339 6.7521431545 ZT8-11 5.95628668 2.8932066215 9.0193667385 ZT12-15 11.284718880749999 10.845107626499999 11.724330134999999 ZT16-19 12.669174645 11.420613705 13.917735585 ZT20-23 19.6230172475 18.67019597 20.575838525