condition mean min max ZT0-3 16.49705 15.675 17.3191 ZT4-7 10.28584 10.28584 10.28584 ZT8-11 9.700165 9.700165 9.700165 ZT12-15 0 0 0 ZT16-19 13.8688 13.8688 13.8688 ZT20-23 15.9141 15.9141 15.9141