condition mean min max ZT0-3 7.399035 6.95998 7.838089999999999 ZT4-7 7.763809999999999 7.763809999999999 7.763809999999999 ZT8-11 14.1202 14.1202 14.1202 ZT12-15 0 0 0 ZT16-19 15.110050000000001 15.110050000000001 15.110050000000001 ZT20-23 11.67015 11.67015 11.67015