condition mean min max ZT0-3 23.23295 19.13615 27.329749999999997 ZT4-7 8.768755 8.768755 8.768755 ZT8-11 4.85252 4.85252 4.85252 ZT12-15 0 0 0 ZT16-19 15.358450000000001 15.358450000000001 15.358450000000001 ZT20-23 19.28555 19.28555 19.28555