condition mean min max ZT0-3 16.930486 16.930486 16.930486 ZT4-7 60.182026 60.182026 60.182026 ZT8-11 15.136333 15.136333 15.136333 ZT12-15 18.16391 18.16391 18.16391 ZT16-19 13.0216605 13.0216605 13.0216605 ZT20-23 13.150872 13.150872 13.150872