condition mean min max ZT0-3 1.836215 1.27471 2.15257 ZT4-7 1.30214 1.30214 1.30214 ZT8-11 1.560025 1.560025 1.560025 ZT12-15 6.0568775 5.883785 6.22997 ZT16-19 3.62095 3.62095 3.62095 ZT20-23 3.22294 3.22294 3.22294