condition mean min max ZT0-3 15.286351 15.286351 15.286351 ZT4-7 13.9244085 13.9244085 13.9244085 ZT8-11 12.5161425 12.5161425 12.5161425 ZT12-15 13.3160865 13.3160865 13.3160865 ZT16-19 12.190410499999999 12.190410499999999 12.190410499999999 ZT20-23 12.331353 12.331353 12.331353