condition mean min max ZT0-3 0.16336590250000002 0.0 0.32673180500000004 ZT4-7 4.59593588675 1.651226047 7.5406457265 ZT8-11 15.004975769249999 13.3022180635 16.707733474999998 ZT12-15 18.82097322 18.25197268 19.38997376 ZT16-19 13.5897566325 12.031960585 15.14755268 ZT20-23 18.34024544 17.373585505 19.306905375