condition mean min max ZT0-3 7.4736575 5.904 9.043315 ZT4-7 4.980285 4.980285 4.980285 ZT8-11 1.7181565 1.7181565 1.7181565 ZT12-15 0 0 0 ZT16-19 6.5850349999999995 6.5850349999999995 6.5850349999999995 ZT20-23 6.115025 6.115025 6.115025