The Joint Committee on Taxation has released Estimate of Federal Tax Expenditures for Fiscal Years 2012-2017 (JCS-1-13):

Tax expenditure analysis can help both
policymakers and the public to understand the actual size of government,
the uses to which government resources are put, and the tax and
economic policy consequences that follow from the implicit or explicit
choices made in fashioning legislation. This report on tax expenditures
for fiscal years 2012-2017 is prepared by the staff of the Joint
Committee on Taxation. … As in the case of earlier reports, the
estimates of tax expenditures in this report were prepared in
consultation with the staff of the Office of Tax Analysis in the
Department of the Treasury.

The Joint Committee staff has made its
estimates (as shown in Table 1) based on the provisions in Federal tax
law as enacted through January 2, 2013. Expired or repealed provisions
are not listed unless they have continuing revenue effects that are
associated with ongoing taxpayer activity. Proposed extensions or
modifications of expiring provisions are not included until they have
been enacted into law. The tax expenditure calculations in this report
are based on the January 2012 Congressional Budget Office revenue
baseline and Joint Committee staff projections of the gross income,
deductions, and expenditures of individuals and corporations for
calendar years 2011-2017.

Part I of this report contains a
discussion of the concept of tax expenditures. Part II is a discussion
of the measurement of tax expenditures. Estimates of tax expenditures
for fiscal years 2012-2017 are presented in Table 1 in Part III. Table 2
shows the distribution of tax returns by income class, and Table 3
presents distributions of selected individual tax expenditures by income
class.