condition mean min max ZT0-3 12.9093 12.9093 12.9093 ZT4-7 7.94079 7.94079 7.94079 ZT8-11 9.508045 9.508045 9.508045 ZT12-15 10.09161 10.09161 10.09161 ZT16-19 17.06075 17.06075 17.06075 ZT20-23 16.49735 16.49735 16.49735