asset accounting

HI SAP guru's

I have some doubts in asset accounting.

(1). how can i configure multiple shift factor for calculating the dep on shift basis.

(2). what is imp of declining method. (one of the calculation method). how the system is calculated the dep with the help depreciation multiplication factor in decling balance method.

(3) what is the imp of change over method.

pls provide real time exp with documentation.

appreciated with reward points.

Thanks& Regards,

ramya.