condition mean min max ZT0-3 61.412157 61.412157 61.412157 ZT4-7 30.9263725 30.9263725 30.9263725 ZT8-11 20.2443315 20.2443315 20.2443315 ZT12-15 24.011817999999998 24.011817999999998 24.011817999999998 ZT16-19 28.193351999999997 28.193351999999997 28.193351999999997 ZT20-23 24.966441 24.966441 24.966441