condition mean min max ZT0-3 266.009402 266.009402 266.009402 ZT4-7 173.5858585 173.5858585 173.5858585 ZT8-11 179.014111 179.014111 179.014111 ZT12-15 185.28106100000002 185.28106100000002 185.28106100000002 ZT16-19 266.7867485 266.7867485 266.7867485 ZT20-23 313.435616 313.435616 313.435616