condition mean min max ZT0-3 9.919868333333334 9.059809999999999 10.586 ZT4-7 8.775414999999999 8.775414999999999 8.775414999999999 ZT8-11 6.683935 6.683935 6.683935 ZT12-15 9.52614 8.784704999999999 10.267575 ZT16-19 9.12389 9.12389 9.12389 ZT20-23 11.509049999999998 11.509049999999998 11.509049999999998