condition mean min max ZT0-3 4.934927500000001 4.85912 5.010735 ZT4-7 4.713615 4.713615 4.713615 ZT8-11 6.448315 6.448315 6.448315 ZT12-15 0 0 0 ZT16-19 9.68208 9.68208 9.68208 ZT20-23 9.52553 9.52553 9.52553