condition mean min max ZT0-3 16.440875000000002 15.5067 17.37505 ZT4-7 13.553 13.553 13.553 ZT8-11 16.20515 16.20515 16.20515 ZT12-15 0 0 0 ZT16-19 19.884700000000002 19.884700000000002 19.884700000000002 ZT20-23 21.762900000000002 21.762900000000002 21.762900000000002