condition mean min max ZT0-3 7.1314525 6.32384 7.939064999999999 ZT4-7 9.812685 9.812685 9.812685 ZT8-11 9.826260000000001 9.826260000000001 9.826260000000001 ZT12-15 0 0 0 ZT16-19 7.248215 7.248215 7.248215 ZT20-23 9.53931 9.53931 9.53931