condition mean min max ZT0-3 8.263186 8.263186 8.263186 ZT4-7 9.230955 9.230955 9.230955 ZT8-11 9.3953995 9.3953995 9.3953995 ZT12-15 9.0192525 9.0192525 9.0192525 ZT16-19 9.386771 9.386771 9.386771 ZT20-23 10.4961345 10.4961345 10.4961345