condition mean min max ZT0-3 1.57026 1.57026 1.57026 ZT4-7 1.20318 1.20318 1.20318 ZT8-11 0.839479 0.839479 0.839479 ZT12-15 1.020728 1.020728 1.020728 ZT16-19 1.1503995 1.1503995 1.1503995 ZT20-23 1.2404950000000001 1.2404950000000001 1.2404950000000001