condition mean min max ZT0-3 10.396926 10.396926 10.396926 ZT4-7 9.924814 9.924814 9.924814 ZT8-11 11.620814 11.620814 11.620814 ZT12-15 10.37489 10.37489 10.37489 ZT16-19 9.157324500000001 9.157324500000001 9.157324500000001 ZT20-23 9.486825 9.486825 9.486825