condition mean min max ZT0-3 6.02258 6.02258 6.02258 ZT4-7 4.4275400000000005 4.4275400000000005 4.4275400000000005 ZT8-11 6.7995350000000006 6.7995350000000006 6.7995350000000006 ZT12-15 9.575690000000002 9.575690000000002 9.575690000000002 ZT16-19 10.411445 10.411445 10.411445 ZT20-23 6.61279 6.61279 6.61279