condition mean min max ZT0-3 11.054944 11.054944 11.054944 ZT4-7 8.814914 8.814914 8.814914 ZT8-11 11.0428695 11.0428695 11.0428695 ZT12-15 10.7071475 10.7071475 10.7071475 ZT16-19 9.3647045 9.3647045 9.3647045 ZT20-23 9.968294499999999 9.968294499999999 9.968294499999999