condition mean min max ZT0-3 1.3643982237499999 1.19776862 1.5310278275 ZT4-7 1.7216802100000002 1.0981847194999999 2.3451757005000005 ZT8-11 4.14185355525 3.2437368105 5.0399703 ZT12-15 7.193631238 6.0093771154999995 8.3778853605 ZT16-19 9.748650765 6.8608444105 12.636457119500001 ZT20-23 16.2352227075 15.319811645 17.15063377