condition mean min max ZT0-3 1.8325193333333334 1.8325193333333334 1.8325193333333334 ZT4-7 0.617484 0.617484 0.617484 ZT8-11 0.656414 0.656414 0.656414 ZT12-15 0.2346465 0.2346465 0.2346465 ZT16-19 1.3244609999999999 1.3244609999999999 1.3244609999999999 ZT20-23 1.141737 1.141737 1.141737