condition mean min max ZT0-3 10.424452 10.424452 10.424452 ZT4-7 10.076769 10.076769 10.076769 ZT8-11 10.5596295 10.5596295 10.5596295 ZT12-15 10.234064499999999 10.234064499999999 10.234064499999999 ZT16-19 9.565673 9.565673 9.565673 ZT20-23 10.340849500000001 10.340849500000001 10.340849500000001