condition mean min max ZT0-3 22.519055015 20.72915896 24.30895107 ZT4-7 20.16565799 18.43525529 21.896060690000002 ZT8-11 22.943629811666668 22.027920153333334 23.85933947 ZT12-15 21.265341575 18.33441048 24.19627267 ZT16-19 14.821969801666665 13.641200563333333 16.002739039999998 ZT20-23 10.479974910333333 9.561135954000001 11.398813866666666