condition mean min max ZT0-3 4.1515450000000005 3.482945 4.820145 ZT4-7 1.879335 1.879335 1.879335 ZT8-11 1.884545 1.884545 1.884545 ZT12-15 0 0 0 ZT16-19 3.583315 3.583315 3.583315 ZT20-23 5.349715 5.349715 5.349715