condition mean min max ZT0-3 19.581733333333332 13.8703 23.25595 ZT4-7 15.45205 15.45205 15.45205 ZT8-11 11.059455 11.059455 11.059455 ZT12-15 13.43745 13.25195 13.62295 ZT16-19 15.440000000000001 15.440000000000001 15.440000000000001 ZT20-23 20.50865 20.50865 20.50865