condition mean min max ZT0-3 18.071728 18.071728 18.071728 ZT4-7 16.9418375 16.9418375 16.9418375 ZT8-11 21.603452500000003 21.603452500000003 21.603452500000003 ZT12-15 22.316218499999998 22.316218499999998 22.316218499999998 ZT16-19 40.29669 40.29669 40.29669 ZT20-23 38.4094225 38.4094225 38.4094225