Given the data, one can only conclude that many treasure this world and its coffers more than they treasure Christ. That they have not sold all and purchased this One Pearl of Great Price.
A couple have passed along articles I've found helpful as we've tried to address the questions we're sometimes receiving.
The Decline and Fall of Charity
Studies like those in Arthur Brooks' Who Really Cares routinely show that churchgoers, particularly conservative evangelicals, comprise the most generous slice of society, yet the generosity and volunteerism of these very people are at historic lows. Moreover, plenty of Americans inside the Church and out think the opposite is true; they take it as a given that charitable giving among the religious is happening at the pace it has in the past.
A Lot of Lattes: Stingy Christians in an Age of Opulence
This is a review of Passing the Plate: Why Americans Don't Give Away More Money. Here's a snippet from the review:
Chapter 2 outlines the dismal reality of what American Christians actually give. Twenty percent of American Christians (19 percent of Protestants; 28 percent of Catholics) give nothing to the church. Among Protestants, 10 percent of evangelicals, 28 percent of mainline folk, 33 percent of fundamentalists, and 40 percent of liberal Protestants give nothing. The vast majority of American Christians give very little—the mean average is 2.9 percent. Only 12 percent of Protestants and 4 percent of Catholics tithe.
A small minority of American Christians give most of the total donated. Twenty percent of all Christians give 86.4 percent of the total. The most generous five percent give well over half (59.6 percent) of all contributions. But higher-income American Christians give less as a percentage of household income than poorer American Christians. In the course of the 20th century, as our personal disposable income quadrupled, the percentage donated by American Christians actually declined.