condition mean min max ZT0-3 14.199279 14.199279 14.199279 ZT4-7 11.7881035 11.7881035 11.7881035 ZT8-11 12.7813485 12.7813485 12.7813485 ZT12-15 13.719857000000001 13.719857000000001 13.719857000000001 ZT16-19 13.946334 13.946334 13.946334 ZT20-23 13.719209 13.719209 13.719209