SAP MM The Table MBEWH Update Logic

MBEWH table is updated whenever there is change in Moving Average Price.

MBEWH is basically the History table for MBEW - Material Valuation table.

As MBEW is supposed to contain current values, when it has to be changed (like when updating material current price, etc.), the current value gets written to MBEWH and the new value gets written to MBEW.

The current standard is always in MBEW. When the first activity in a ‘period’ takes place valuation or quantity update; a record is written to MBEWH to document the balance, std, price control, that existed BEFORE the "first activity 

The number that represents the previous period record being written into the MBEWH table is represented in the ‘current period’ LFMON field. 

EXAMPLE: when the first activity occurs in period 3 (i.e., a goods receipt), an entry is written into the MBEWH table with a ‘current period’ number of 2. The quant and value updated to the ‘total stock’ and ‘total value’ fields are equal to the data that represents these fields PRIOR to the activity quant and value occurring in period 3.

If there is no activity for several periods, you will not have entries for every period in the MBEWH table.