Foreclosure filings in the United States jumped in July, again setting a record for the third time in five months. The increase was due to falling home prices and the recession, which kept some homeowners from making payments or refinancing.

Question: How is the U.S. savings rate, which has gone from near zero percent in the past to 6.9 percent recently, determined? And a more elaborate question: Is it truly the difference between what is earned and what is…