Will people go on giving funds to charities if the nation adopts a flat tax and contributions can no longer be deducted? There is substantial evidence that they will, studies show.

• An estimated 64 percent of those who give to charities don't even claim a deduction for their contributions.

• Those giving to the arts are more likely to itemize than those giving to human services.

• Some 14 percent of households with a net worth between $5,000 and $25,000 give, on average, $158 a year.

• This compares to 83.6 percent of households with a net worth of $1 million to $10 million -- who give $7,784 on average.

The figures are from a study by Boston College sociologists Paul G. Schervish and John J. Havens.

• They found that married donors give almost twice as much as a percentage of income as unmarried donors.

• On average, older people give a greater portion of their income than younger ones.

Although the top marginal tax rate has fluctuated from 28 percent to 91 percent in the past two decades, individual donations to charities have remained at about 1.83 percent of personal income.

The Heritage Foundation contends that giving would actually rise under a flat tax system. It reasons that a flat tax would drive up income. Since the wealthier people are, the more generous they can be, Heritage estimates that giving would be 3.8 percent higher under a 17 percent flat tax.

Source: Perspective, "Giving It Away," Investor's Business Daily, January 31, 1997.