condition mean min max ZT0-3 11.585626 11.585626 11.585626 ZT4-7 14.972873 14.972873 14.972873 ZT8-11 15.781462000000001 15.781462000000001 15.781462000000001 ZT12-15 15.519524 15.519524 15.519524 ZT16-19 17.172811 17.172811 17.172811 ZT20-23 18.672916999999998 18.672916999999998 18.672916999999998