condition mean min max ZT0-3 9.594505 9.594505 9.594505 ZT4-7 8.24069 8.24069 8.24069 ZT8-11 8.895465000000002 8.895465000000002 8.895465000000002 ZT12-15 10.9724 10.9724 10.9724 ZT16-19 12.1608 12.1608 12.1608 ZT20-23 9.840595 9.840595 9.840595