condition mean min max ZT0-3 7.54206 7.54206 7.54206 ZT4-7 7.038055 7.038055 7.038055 ZT8-11 4.8059899999999995 4.8059899999999995 4.8059899999999995 ZT12-15 5.265305 5.265305 5.265305 ZT16-19 6.182515 6.182515 6.182515 ZT20-23 6.234685000000001 6.234685000000001 6.234685000000001