Physical and emotional changes account for most of the difficulty.

That change probably accounted for two dozen cases a year.

A change in the way securities dealers must account for certificates they hold would raise $2.5 billion.

War, disease or climatic change could account for such a throwback.

Mortgage rate changes account for the majority of the gap.

This change accounted for 85 percent of the increase in the number of people with health insurance.

Such a change might account for the recent drop in the number of new cases.

Experts said these methodological changes could account for the different results.

Several changes in immigration laws and regulations account for part of the increase.

Intel hasn't announced exactly what changes account for the performance boost.