condition mean min max ZT0-3 6.528431 6.528431 6.528431 ZT4-7 8.131808 8.131808 8.131808 ZT8-11 8.929081499999999 8.929081499999999 8.929081499999999 ZT12-15 10.441909 10.441909 10.441909 ZT16-19 10.339737 10.339737 10.339737 ZT20-23 11.416592999999999 11.416592999999999 11.416592999999999