condition mean min max ZT0-3 6.101514999999999 6.101514999999999 6.101514999999999 ZT4-7 5.57208 5.57208 5.57208 ZT8-11 6.14603 6.14603 6.14603 ZT12-15 6.765264999999999 6.765264999999999 6.765264999999999 ZT16-19 5.77361 5.77361 5.77361 ZT20-23 6.382655 6.382655 6.382655