condition mean min max ZT0-3 660.410642 660.410642 660.410642 ZT4-7 280.62860950000004 280.62860950000004 280.62860950000004 ZT8-11 441.838798 441.838798 441.838798 ZT12-15 507.70388549999996 507.70388549999996 507.70388549999996 ZT16-19 806.5939900000001 806.5939900000001 806.5939900000001 ZT20-23 571.665287 571.665287 571.665287