condition mean min max ZT0-3 8.179435 8.179435 8.179435 ZT4-7 6.71841 6.71841 6.71841 ZT8-11 6.597049999999999 6.597049999999999 6.597049999999999 ZT12-15 8.18441 8.18441 8.18441 ZT16-19 7.999805 7.999805 7.999805 ZT20-23 8.312619999999999 8.312619999999999 8.312619999999999