condition mean min max ZT0-3 6.5868199999999995 6.5868199999999995 6.5868199999999995 ZT4-7 5.57071 5.57071 5.57071 ZT8-11 4.39601 4.39601 4.39601 ZT12-15 5.5673449999999995 5.5673449999999995 5.5673449999999995 ZT16-19 6.563124999999999 6.563124999999999 6.563124999999999 ZT20-23 6.386615 6.386615 6.386615