condition mean min max ZT0-3 338.124905 338.124905 338.124905 ZT4-7 186.230328 186.230328 186.230328 ZT8-11 216.216321 216.216321 216.216321 ZT12-15 257.682796 257.682796 257.682796 ZT16-19 231.357525 231.357525 231.357525 ZT20-23 263.050012 263.050012 263.050012