condition mean min max ZT0-3 3825.793528 3825.793528 3825.793528 ZT4-7 4027.056667 4027.056667 4027.056667 ZT8-11 3776.0453964999997 3776.0453964999997 3776.0453964999997 ZT12-15 3760.669858 3760.669858 3760.669858 ZT16-19 3101.174587 3101.174587 3101.174587 ZT20-23 2571.2825860000003 2571.2825860000003 2571.2825860000003