condition mean min max ZT0-3 2074.622922 2074.622922 2074.622922 ZT4-7 1647.885463 1647.885463 1647.885463 ZT8-11 955.826331 955.826331 955.826331 ZT12-15 759.4699545000001 759.4699545000001 759.4699545000001 ZT16-19 660.03724 660.03724 660.03724 ZT20-23 869.234157 869.234157 869.234157