These pressures have been supplemented by shifts in income toward the oil-exporting countries, which more recently have built surpluses because of steep increases in oil prices. The changes in shares of world GDP, however, have had little effect  1  Under current law, those longer-run pressures on the federal budget threaten to place the economy on an unsustainable path.
Large deficits could result in rising interest rates and ever-growing interest payments on the accumulating stock of debt, which in turn would further augment deficits in future years. That process could result in deficits as a percentage of gross domestic product rising without limit.