Inventory Pricing

Hi, why is it when entering inventory items the levels a, b, c, ETC reflect the base selling price of the previous entered item, can i suggest that when entering new items all price levels reflect the new items 'base price' and doesn't pick up on the preivous items 'base' price.

IE: i create inventory item 'XY' with a base sell price of $40, i then create another inventory item of 'XYZ' with a base sell price of $100 yet levels a, b, c ETC have automatically been populated with $40.