condition mean min max ZT0-3 6.617153333333333 5.408060000000001 8.739745 ZT4-7 5.52303 5.52303 5.52303 ZT8-11 4.994435 4.994435 4.994435 ZT12-15 6.2945150000000005 5.373635 7.215395 ZT16-19 5.380625 5.380625 5.380625 ZT20-23 6.55183 6.55183 6.55183