condition mean min max ZT0-3 1.5983133333333335 1.5983133333333335 1.5983133333333335 ZT4-7 1.145925 1.145925 1.145925 ZT8-11 0.98544 0.98544 0.98544 ZT12-15 1.4414799999999999 1.4414799999999999 1.4414799999999999 ZT16-19 1.5549000000000002 1.5549000000000002 1.5549000000000002 ZT20-23 3.31971 3.31971 3.31971