condition mean min max ZT0-3 32.852875 31.10865 34.5971 ZT4-7 13.29185 13.29185 13.29185 ZT8-11 9.98917 9.98917 9.98917 ZT12-15 0 0 0 ZT16-19 7.544531 7.544531 7.544531 ZT20-23 15.45475 15.45475 15.45475