condition mean min max ZT0-3 12.518565 12.518565 12.518565 ZT4-7 12.9232275 12.9232275 12.9232275 ZT8-11 11.754323500000002 11.754323500000002 11.754323500000002 ZT12-15 10.711811 10.711811 10.711811 ZT16-19 12.3599325 12.3599325 12.3599325 ZT20-23 11.366324500000001 11.366324500000001 11.366324500000001