condition mean min max ZT0-3 17.933217 17.933217 17.933217 ZT4-7 26.582235 26.582235 26.582235 ZT8-11 30.075564 30.075564 30.075564 ZT12-15 32.9224445 32.9224445 32.9224445 ZT16-19 21.8339395 21.8339395 21.8339395 ZT20-23 20.760619 20.760619 20.760619