condition mean min max ZT0-3 10.208937500000001 9.98834 10.429535 ZT4-7 15.0909 15.0909 15.0909 ZT8-11 15.2819 15.2819 15.2819 ZT12-15 0 0 0 ZT16-19 18.3199 18.3199 18.3199 ZT20-23 13.7253 13.7253 13.7253