Federally insured credit unions making corporate assessment payments received some good news from the NCUA Thursday: the high end of projected Stabilization Fund assessments declined $400 million during the first half of 2012.

The reduced corporate bill is the result of legacy asset performance and the macroeconomic factors used to project their future performance, the NCUA said in a release.

The estimated range of total assessments is now between $6 billion and $8.9 billion, down from between $6 billion and $9.3 billion as of last Dec. 31.

Credit unions have already paid $4.1 billion in corporate assessments, which means remaining assessments are projected to range between $1.9 billion and $4.8 billion until the Stabilization Fund expires in 2021.

Corporate stabilization statements and other financial information regarding corporate legacy assets an NCUA Guaranteed Notes is available on the NCUA's website.

“NCUA is committed to periodically updating the estimates about the losses associated with the Corporate System Resolution, which will vary over time, and the total anticipated assessments that credit unions will pay during the life of the Stabilization Fund,” Chairman Debbie Matz said in the announcement.

“The latest forecasts indicate that the top end of the range of total Stabilization Fund assessments has declined by $400 million during the last six months,” Matz said.

Forecasting borrower behavior and changes in the economic environment is challenging, the NCUA said. Factors include changes in housing prices, interest rates, unemployment rates and mortgage prepayments. The NCUA uses BlackRock, an independent securities valuation firm, to project the future performance of the legacy assets in the NGNs.

 The NCUA said in the release that net proceeds from more than $170 million in legal settlements, which would include a 25% hit in contingency legal fees revealed last month, are included in the new assessment estimates.