condition mean min max ZT0-3 6736.237792 6736.237792 6736.237792 ZT4-7 6553.8601165 6553.8601165 6553.8601165 ZT8-11 7461.7137084999995 7461.7137084999995 7461.7137084999995 ZT12-15 7950.827412500001 7950.827412500001 7950.827412500001 ZT16-19 6837.02131 6837.02131 6837.02131 ZT20-23 5712.337439 5712.337439 5712.337439