condition mean min max ZT0-3 17.24701 17.24701 17.24701 ZT4-7 17.950165 17.950165 17.950165 ZT8-11 18.4494445 18.4494445 18.4494445 ZT12-15 15.739614 15.739614 15.739614 ZT16-19 15.550367 15.550367 15.550367 ZT20-23 15.454363 15.454363 15.454363