condition mean min max ZT0-3 9.462413 9.462413 9.462413 ZT4-7 9.1435475 9.1435475 9.1435475 ZT8-11 9.735316999999998 9.735316999999998 9.735316999999998 ZT12-15 10.002644 10.002644 10.002644 ZT16-19 9.753857 9.753857 9.753857 ZT20-23 10.39713 10.39713 10.39713