condition mean min max ZT0-3 3.3341775 3.271965 3.3963900000000002 ZT4-7 4.95015 4.95015 4.95015 ZT8-11 5.50822 5.50822 5.50822 ZT12-15 0 0 0 ZT16-19 5.1644749999999995 5.1644749999999995 5.1644749999999995 ZT20-23 5.77685 5.77685 5.77685