Japanese housing starts have fallen sharply in recent months, just as housing-related markets in the United States have declined since the advent of the subprime mortgage crisis. But the backgrounds of the two slumps are totally different.

In July, Japanese housing starts sank to 950,000 units per annum, down roughly 30 percent from 1.35 million units in June. In August they dropped another 20 percent to 750,000 units per annum. The August figure represents a plunge of more than 40 percent from a year ago.

In the meantime, housing-related investment in the United States fell 16.3 percent in the first quarter, 11.8 percent in the second quarter and 20.1 percent in the third quarter — all on a year-on-year basis.