condition mean min max ZT0-3 20.196481 20.196481 20.196481 ZT4-7 22.157981 22.157981 22.157981 ZT8-11 23.836586500000003 23.836586500000003 23.836586500000003 ZT12-15 22.977484 22.977484 22.977484 ZT16-19 24.846352 24.846352 24.846352 ZT20-23 25.019399 25.019399 25.019399