condition mean min max ZT0-3 10.967421 10.967421 10.967421 ZT4-7 9.7338395 9.7338395 9.7338395 ZT8-11 9.784076500000001 9.784076500000001 9.784076500000001 ZT12-15 10.618402 10.618402 10.618402 ZT16-19 10.1910345 10.1910345 10.1910345 ZT20-23 10.971879 10.971879 10.971879