condition mean min max ZT0-3 499.281818 499.281818 499.281818 ZT4-7 354.56064 354.56064 354.56064 ZT8-11 478.520345 478.520345 478.520345 ZT12-15 385.2705185 385.2705185 385.2705185 ZT16-19 613.305466 613.305466 613.305466 ZT20-23 476.847441 476.847441 476.847441