condition mean min max ZT0-3 5.4291596625 4.7422290480000004 6.116090277 ZT4-7 6.22955772425 5.6245816125 6.834533836 ZT8-11 9.41967359575 7.7174437555 11.121903436 ZT12-15 12.30331856 11.80509017 12.801546949999999 ZT16-19 12.4912445525 11.810209365 13.17227974 ZT20-23 14.6716699125 14.2419933 15.101346525