So our conclusion is that the net stimulus to short-term GDP will not be zero, and will be positive, but the stimulus is likely to be modest in magnitude. Some economists have assumed that every $1 billion spent by the government through the stimulus package would raise short-term GDP by $1.5 billion. Or, in economics jargon, that the multiplier is 1.5.

That seems too optimistic given the nature of the spending programs being proposed. We believe a multiplier well below one seems much more likely…

The increased federal debt caused by this stimulus package has to be paid for eventually by higher taxes on households and businesses. Higher income and business taxes generally discourage effort and investments, and result in a larger social burden than the actual level of the tax revenue needed to finance the greater debt. The burden from higher taxes down the road has to be deducted both from any short-term stimulus provided by the spending program, and from its long-run effects on the economy.