Invesco’s (NYSE: IVZ) PowerShares, the fourth-largest U.S. exchange traded funds issuer, today announced name, index and investment objective changes for three of its municipal bond ETFs.

“Effective July 8, 2014, the PowerShares Insured National Municipal Bond Portfolio (NYSEArca: PZA) will track the BofA ML National Long-Term Core Plus Municipal Securities Index (UNAP), the PowerShares Insured New York Municipal Bond Portfolio (NYArca: PZT) will track the BofA ML New York Long-Term Core Plus Municipal Securities Index (UNYP) and the PowerShares Insured California Municipal Bond Portfolio (NYSEArca: PWZ) will track the BofA ML California Long-Term Core Plus Municipal Securities Index (UCAP),” said PowerShares in a statement.

PZA, which debuted in October 2007, charges 0.28% per year and has $642 million in assets under management. The ETF currently has a 30-day SEC yield of 3.2% and an effective duration of 7.9 years.

PZT also has an annual expense ratio of 0.28% with a 30-day SEC yield of 2.78% and an effective duration of 7.2 years. The $55.1 million PWZ has a 30-day SEC yield of 2.7% and an effective duration of 6.76 years. Like PZA and PZT, PWZ debuted in October 2007 and charges 0.28% per year.

“Since 2007, when the PowerShares Insured Municipal Bond Portfolios first listed, the US market for insured municipal bond securities has shrunk by over 40 percent, making the available supply of insured-municipal securities more limited. The new indexes underlying the PowerShares’ Municipal Bond ETFs include both insured and uninsured municipal bonds,” according to PowerShares.

Table Courtesy: PowerShares

ETF Trends editorial team contributed to this post.