condition mean min max ZT0-3 98.176321 98.176321 98.176321 ZT4-7 140.327877 140.327877 140.327877 ZT8-11 121.7019635 121.7019635 121.7019635 ZT12-15 101.1322415 101.1322415 101.1322415 ZT16-19 71.7617075 71.7617075 71.7617075 ZT20-23 47.6542845 47.6542845 47.6542845