condition mean min max ZT0-3 4.64919 4.64919 4.64919 ZT4-7 3.3627849999999997 3.3627849999999997 3.3627849999999997 ZT8-11 4.82735 4.82735 4.82735 ZT12-15 6.40485 6.40485 6.40485 ZT16-19 8.362645 8.362645 8.362645 ZT20-23 5.191205 5.191205 5.191205