There are numerous factors that determine a processor's retail price. Below are some of them.
1. The first is cost to produce the processor.
2. The intended purchaser or market segment.
3. How many cores the CPU has and what the maximum frequency it can run at reliably.
4. The processor's performance compared to other competitor's products
5. Supply and demand
May I ask how you know this information? Maybe give a little background of your expertise.