condition mean min max ZT0-3 0.59040635 0.363602617 0.817210083 ZT4-7 3.8327125972500005 2.5835539665 5.081871228000001 ZT8-11 10.887601310500001 8.437232291 13.337970330000001 ZT12-15 26.292494797499998 22.327774759999997 30.257214835 ZT16-19 23.98523582 23.42471054 24.5457611 ZT20-23 24.3806616625 24.375696724999997 24.385626600000002