condition mean min max ZT0-3 30.839192 30.839192 30.839192 ZT4-7 41.9748805 41.9748805 41.9748805 ZT8-11 30.157554 30.157554 30.157554 ZT12-15 30.221176999999997 30.221176999999997 30.221176999999997 ZT16-19 30.641302500000002 30.641302500000002 30.641302500000002 ZT20-23 27.924947500000002 27.924947500000002 27.924947500000002