condition mean min max ZT0-3 10.258708333333333 7.98786 12.1735 ZT4-7 9.308924999999999 9.308924999999999 9.308924999999999 ZT8-11 11.948695 11.948695 11.948695 ZT12-15 21.1468 20.934199999999997 21.3594 ZT16-19 17.6217 17.6217 17.6217 ZT20-23 16.204050000000002 16.204050000000002 16.204050000000002