The payments now account for nearly half of the nation's expanding agricultural subsidy system, a complex web that has little basis in fairness or efficiency. What began in the 1930s as a limited safety net for working farmers has swollen into a far-flung infrastructure of entitlements that has cost $172 billion over the past decade. In 2005 alone, when pretax farm profits were at a near-record $72 billion, the federal government handed out more than $25 billion in aid, almost 50 percent more than the amount it pays to families receiving welfare.