condition mean min max ZT0-3 13.2408 12.31515 14.166450000000001 ZT4-7 12.92285 12.92285 12.92285 ZT8-11 15.827950000000001 15.827950000000001 15.827950000000001 ZT12-15 0 0 0 ZT16-19 17.4436 17.4436 17.4436 ZT20-23 17.97265 17.97265 17.97265