condition mean min max ZT0-3 7.870725 7.164105 8.577345 ZT4-7 8.51472 8.51472 8.51472 ZT8-11 13.6965 13.6965 13.6965 ZT12-15 0 0 0 ZT16-19 12.74175 12.74175 12.74175 ZT20-23 10.039525000000001 10.039525000000001 10.039525000000001