condition mean min max ZT0-3 13.844453 13.844453 13.844453 ZT4-7 13.857216000000001 13.857216000000001 13.857216000000001 ZT8-11 16.8845915 16.8845915 16.8845915 ZT12-15 13.1453195 13.1453195 13.1453195 ZT16-19 14.647467 14.647467 14.647467 ZT20-23 12.9023575 12.9023575 12.9023575