In comparison to the large variety of stock indices there are only a few bond indices.

The Lehman Brothers investment bank developed the four most popular indices.

• Lehman Brothers Government Bond Index

This index includes US government bonds that are set to mature in more than a year.

Index Target:  The government sector of the US bond market.

• Lehman Brothers Credit Bond Index

This index is made up of corporate bonds rated BBB and higher.

Index Target:  The corporate sector of the US bond market.

• Lehman Brothers Government / Credit Bond Index

This index includes both of the previous indices in the following makeup:

• 55% Government Bonds
• 45% Corporate Bonds

Index Target:  The government and corporate sectors of the US bond market.

• Lehman Brothers Aggregate Bond Index

This index includes government, corporate, and mortgage-backed bonds.

Index Target:  The entire US bond market.