condition mean min max ZT0-3 371.515271 371.515271 371.515271 ZT4-7 505.99446950000004 505.99446950000004 505.99446950000004 ZT8-11 545.056236 545.056236 545.056236 ZT12-15 495.6303715 495.6303715 495.6303715 ZT16-19 466.421693 466.421693 466.421693 ZT20-23 248.71105749999998 248.71105749999998 248.71105749999998