Why Bond Prices Go DOWN When Interest Rates Go UP

Simple math can explain this. Here is an example: You have a bond with a face value of $1,000 that pays 5% every year, or $50. When the bond matures you receive $1,000. Now imagine that interest rates have jumped to 7%, so a new $1,000 bond pays $70 every year. What happens to the value of your 5% bond?