condition mean min max ZT0-3 15.170560551 12.644367862 17.69675324 ZT4-7 7.84646256425 6.8791975035 8.813727625 ZT8-11 10.026293377250001 7.8422253495000005 12.210361405 ZT12-15 17.5142210175 14.554552215000001 20.47388982 ZT16-19 19.195494285000002 17.638649965 20.752338605000002 ZT20-23 24.754757507500003 24.5849533 24.924561715000003