condition mean min max ZT0-3 995.232057 995.232057 995.232057 ZT4-7 1681.6837150000001 1681.6837150000001 1681.6837150000001 ZT8-11 2136.804853 2136.804853 2136.804853 ZT12-15 1973.9427839999998 1973.9427839999998 1973.9427839999998 ZT16-19 1635.693595 1635.693595 1635.693595 ZT20-23 1229.809519 1229.809519 1229.809519