condition mean min max ZT0-3 135.616672 135.616672 135.616672 ZT4-7 129.342443 129.342443 129.342443 ZT8-11 154.1752485 154.1752485 154.1752485 ZT12-15 128.43007 128.43007 128.43007 ZT16-19 116.484459 116.484459 116.484459 ZT20-23 66.075634 66.075634 66.075634