condition mean min max ZT0-3 1136.511985 1136.511985 1136.511985 ZT4-7 989.630865 989.630865 989.630865 ZT8-11 805.4857705 805.4857705 805.4857705 ZT12-15 1086.8837815 1086.8837815 1086.8837815 ZT16-19 913.7559085 913.7559085 913.7559085 ZT20-23 918.8601255000001 918.8601255000001 918.8601255000001