condition mean min max ZT0-3 0.02353615 0.02353615 0.02353615 ZT4-7 0.0273659 0.0273659 0.0273659 ZT8-11 0.0 0.0 0.0 ZT12-15 0.0 0.0 0.0 ZT16-19 0.02419775 0.02419775 0.02419775 ZT20-23 0.03586015 0.03586015 0.03586015