condition mean min max ZT0-3 12.7231488305 9.250301381 16.19599628 ZT4-7 5.21736205825 4.1986529025 6.236071214 ZT8-11 5.6675563215 5.3439429705000006 5.9911696725 ZT12-15 5.930844247 4.747345391 7.114343103 ZT16-19 13.072174556500002 10.257945968000001 15.886403145000001 ZT20-23 27.938225862499998 25.84638772 30.030064005