condition mean min max ZT0-3 2.0137590000000003 1.009142 3.524455 ZT4-7 2.599125 2.599125 2.599125 ZT8-11 1.9402249999999999 1.9402249999999999 1.9402249999999999 ZT12-15 5.452755 4.3451 6.56041 ZT16-19 4.3538250000000005 4.3538250000000005 4.3538250000000005 ZT20-23 2.1841150000000003 2.1841150000000003 2.1841150000000003