condition mean min max ZT0-3 13.844453 13.844453 13.844453 ZT4-7 11.6852865 11.6852865 11.6852865 ZT8-11 11.901743 11.901743 11.901743 ZT12-15 10.665644499999999 10.665644499999999 10.665644499999999 ZT16-19 11.8769875 11.8769875 11.8769875 ZT20-23 12.4734585 12.4734585 12.4734585