condition mean min max ZT0-3 0.5374775 0.0 1.074955 ZT4-7 8.824404999999999 8.824404999999999 8.824404999999999 ZT8-11 6.6577399999999995 6.6577399999999995 6.6577399999999995 ZT12-15 0 0 0 ZT16-19 9.751965 9.751965 9.751965 ZT20-23 5.44604 5.44604 5.44604