condition mean min max ZT0-3 793.216487 793.216487 793.216487 ZT4-7 897.0476665 897.0476665 897.0476665 ZT8-11 1140.131973 1140.131973 1140.131973 ZT12-15 966.8196330000001 966.8196330000001 966.8196330000001 ZT16-19 1117.159079 1117.159079 1117.159079 ZT20-23 991.5717305000001 991.5717305000001 991.5717305000001