condition mean min max ZT0-3 8.93442 8.80292 9.06592 ZT4-7 8.373405 8.373405 8.373405 ZT8-11 10.563945 10.563945 10.563945 ZT12-15 0 0 0 ZT16-19 13.37305 13.37305 13.37305 ZT20-23 10.76375 10.76375 10.76375