condition mean min max ZT0-3 5.1930475000000005 5.17464 5.211455 ZT4-7 4.386055 4.386055 4.386055 ZT8-11 10.035655 10.035655 10.035655 ZT12-15 0 0 0 ZT16-19 8.96001 8.96001 8.96001 ZT20-23 7.269355 7.269355 7.269355