Wealthy Americans scaled back their charitable contributions nearly 35 percent in 2009, a recently released study of wealthy households shows.

The Bank of America Merrill Lynch Study of High Net Worth Philanthropy for 2010 found that average charitable giving dropped from $83,034 in 2007 to $54,016 in 2009, after adjusting for inflation.

Wealthy philanthropists drew the purse strings tightest on health organizations, where the average gift dropped 63.7 percent, from $12,430 to $4,511.

The study, conducted every two years in partnership with the Center on Philanthropy at Indiana University, examines the habits of wealthy households, which account for about half of all charitable giving in the United States.

Researchers surveyed more than 800 randomly selected households where income was greater than $200,000 per year, or net worth, excluding the value of the primary residence, was at least $1 million. The average wealth of respondents was more than $10 million, and half of them had a net worth between $3 million and $20 million.

The decline in giving reflected wealthy people’s own financial situations. Although total charitable dollars fell, giving as a portion of income remained somewhat steady at 9 percent, compared with 11 percent in 2007.

Wealthy philanthropists appeared to adjust their priorities in response to the recession. The portion who gave to basic human needs rose from 75 percent in 2007 to 85 percent in 2009.

Some types of not-for-profits received bigger gifts on average. Arts, which are already supported to a greater degree by wealthy people, saw the average gift rise 11.6 percent, to $5,531. Gifts to international causes and the environment and animals grew as well.

Tax issues are a significant motivator, researchers found. About two-thirds, or 67 percent, of wealthy households reported that they would somewhat or dramatically decrease their contributions if they were to receive zero income-tax deductions. That was up from 47 percent in 2007.

If the estate tax were repealed, 43 percent of wealthy households would somewhat or dramatically increase the amount they leave to charity. That was up from 36 percent in 2007.