condition mean min max ZT0-3 10.098147 10.098147 10.098147 ZT4-7 10.6295015 10.6295015 10.6295015 ZT8-11 10.78782 10.78782 10.78782 ZT12-15 9.806780499999999 9.806780499999999 9.806780499999999 ZT16-19 10.2485265 10.2485265 10.2485265 ZT20-23 10.03393 10.03393 10.03393