This is a break down of the costs spent per campaign. You can identify the campaigns that consume the most PPC costs.
Use this Free Tool For Calculating Amazon PPC, ACos Cost
Automatic campaigns mostly take in the largest slice of the PPC costs.
The target group of automatic campaigns are also very vague, Amazon automatically identifies keywords from your product listing and deducts money from your daily bid for each click to your product. Sometimes you might exhaust your entire day’s bid early in the morning.
Most high performing Amazon PPC campaigns are successful due to a comprehensive keyword research, continuous management and maintenance, and an organized logical structure.
A good strategy for effective bidding is to bid highest for exact matches, then for phrase matches and lastly for broad matches. By doing this, you will be bidding highest for most relevant searches.