condition mean min max ZT0-3 9746.253397 9746.253397 9746.253397 ZT4-7 8987.3705555 8987.3705555 8987.3705555 ZT8-11 7271.903883999999 7271.903883999999 7271.903883999999 ZT12-15 8940.95409 8940.95409 8940.95409 ZT16-19 8683.871839 8683.871839 8683.871839 ZT20-23 7987.391959500001 7987.391959500001 7987.391959500001