condition mean min max ZT0-3 12.116576 12.116576 12.116576 ZT4-7 13.471733 13.471733 13.471733 ZT8-11 12.609835499999999 12.609835499999999 12.609835499999999 ZT12-15 10.3312125 10.3312125 10.3312125 ZT16-19 11.5102215 11.5102215 11.5102215 ZT20-23 11.317472500000001 11.317472500000001 11.317472500000001