condition mean min max ZT0-3 8.545015 8.545015 8.545015 ZT4-7 9.940576 9.940576 9.940576 ZT8-11 10.062993 10.062993 10.062993 ZT12-15 11.0896635 11.0896635 11.0896635 ZT16-19 10.0733165 10.0733165 10.0733165 ZT20-23 9.6954145 9.6954145 9.6954145