condition mean min max ZT0-3 8.456984 8.456984 8.456984 ZT4-7 11.6274515 11.6274515 11.6274515 ZT8-11 10.4908265 10.4908265 10.4908265 ZT12-15 10.0434685 10.0434685 10.0434685 ZT16-19 8.0517605 8.0517605 8.0517605 ZT20-23 9.646256000000001 9.646256000000001 9.646256000000001