condition mean min max ZT0-3 5.04879 5.04879 5.04879 ZT4-7 3.949705 3.949705 3.949705 ZT8-11 3.85934 3.85934 3.85934 ZT12-15 4.795755 4.795755 4.795755 ZT16-19 6.00464 6.00464 6.00464 ZT20-23 4.867115 4.867115 4.867115