Professor Paul Zarowin - NYU Stern School of Business
Financial Reporting and Analysis - B10.2302/C10.0021 - Class Notes
Income Taxes
The key feature that drives accounting for income taxes is that pre-tax taxable income (what the firm reports to
the IRS) generally does not equal pre-tax book (financial statement) income, due to 2 types of differences, temporary
differences and permanent differences.
Thus: book income = taxable income ± temporary differences ± permanent differences.
As we know, book income is measured according to the accrual principal, wherein revenue and expense recognition
need not follow the flow of cash. The IRS calculates taxable income on a cash basis (virtually).
Temporary (timing) differences between book vs. taxable income are due to items of revenue or expense that are
recognized in one period for taxes, but in a different period for books. Book recognition can come either before
or after tax recognition. These revenue and expense items cause a timing difference between the two incomes, but
over the "long run", they cause no difference between the two incomes. This is why they are temporary.
When the difference first arises it is called an originating timing difference; when it later reverses it is called
a reversing timing difference. Examples of temporary differences are: (1) computing depreciation expense by the
SL method for books and by an accelerated method for taxes, and (2) computing bad debts expense by the allowance
method for books and by the direct write-off method for taxes. Over the life of the firm, total depreciation expense
and bad debts expense are unaffected by the method. What is affected is how much expense is recognized in any given
period. Temporary differences are said to "reverse", because if they cause book income to be higher (lower)
than taxable income in one period, they must cause taxable income to be higher (lower) than book income in another
period.
Permanent differences are differences that never reverse. That is, they are items of book (or tax) revenue or expense
in one period, but they are never items of tax (or book) revenue or expense. They are either non-taxable revenues
(book revenues that are non-taxable) or non-deductible expenses (book expenses that are non-deductible). Examples
of permanent differences are (non- taxable) interest revenue on municipal bonds and (non-deductible) goodwill (GW)
amortization expense under the purchase method for acquisitions.
Temporary differences cause deferred taxes, while permanent differences cause a firm's effective income tax rate
(book income tax expense ÷ pre-tax book income) to differ from the statutory tax rate. We will first discuss
temporary differences and then permanent differences.
Temporary Differences: Deferred Taxes
Accounting for temporary differences is called deferred tax accounting or inter-period tax allocation. The terms
refer to the fact that the total income tax expense recognized for books in a given period can be paid to the IRS
over different periods (both before, during, and after book recognition); alternatively, the amount of tax (cash)
paid to the IRS in a given period is recognized as book tax expense over different periods.
Deferred Tax Assets and Liabilities
What drives deferred tax accounting is (the changes in) the deferred tax asset and liability accounts. Deferred
tax liabilities are liabilities for taxes due in the future (future cash outflow for taxes payable) on income that
has already been recognized for books. In effect, although you have already recognized the income on your books,
the IRS lets you pay the taxes later (due to the timing difference). Deferred tax assets are reductions in future
taxes payable, because you have already paid the taxes on book income to be recognized in the future (like a prepaid
tax).
Because of the matching principle, we care about the total income tax expense to be matched against pre-tax book
income, regardless of whether this expense involves a current cash outflow or not (just like any other expense
under the accrual method). Under accrual accounting, not all expenses involve current cash outflows; some expenses
(prepayments:assets) involve past cash outflows, and some expenses involve future cash outflows (payables:liabilities).
One way to think about deferred tax assets and liabilities is: because of the timing differences between tax and
financial reporting, some of this period's (book) income tax expense has been (pre)paid in prior periods, having
caused a deferred tax asset when paid, that we now draw down (reducing current cash outflow); some of this period's
income tax expense will be paid in the future, causing a deferred tax liability now (also reducing current cash
outflow). Some of the income tax expense is being currently paid, so it does not cause deferred tax assets or liabilities.
Another way to think about deferred tax assets and liabilities is: some of the current tax cash outflow is paying
for current taxes; some of the outflow is paying for past taxes (paying off a deferred tax liability); and some
is paying for future taxes (building up a deferred tax asset).
The following table shows how the timing difference between book vs. tax revenue and expense and recognition causes
deferred tax assets and liabilities. Simultaneous recognition (paying cash for current tax expense), of course,
does not cause deferred taxes. There are thus 4 possible cases.
Revenues Expenses
recognize for books
before taxes 1.Deferred tax liability 2.Deferred tax asset
recognize for taxes
before books 3. Deferred tax asset 4. Deferred tax liability
In case 1, you show revenue for books now, but you will pay taxes on it in the future, causing a deferred tax liability
(future cash outflow, increase in future taxes payable). In case 2, you show expenses for books now, but you will
get the tax deduction in the future, causing a deferred tax asset (current cash outflow, reduction in future taxes
payable). In case 3, you pay taxes now, on book revenues that you will recognize in the future causing a deferred
tax asset (a prepaid tax, reduction in future taxes payable). In case 4, you take a tax deduction now for a future
book expense, so you will have to pay more taxes in the future, causing a deferred tax liability (future cash outflow,
increase in future taxes payable).
An example of #1 is an installment sale; revenue is recognized up front for financial reporting, but is recognized
for tax purposes later, when cash is received each period.
An example of #2 is bad debts expense. The allowance method for books recognizes the expense in the period of sale
by the adjusting entry (matching principle), while the direct write-off method
recognizes the expense in a later period, when the receivable is actually written off.
An example of #3 is a prepayment where revenue is recognized for tax purposes up front as cash is received , while
accrual accounting delays revenue recognition until revenue is earned later.
An example of #4 is depreciation expense; firms use an accelerated method for taxes and SL for books. This combination
recognizes some depreciation for taxes first and for books later.
RCJ give additional examples of revenues and expenses that produce deferred tax assets and liabilities in Table
12.1 on page 609.
Total Income Tax Expense on the I/S is the sum of 2 components, current plus deferred, either one of which (or
both) can be positive or negative. The current part is the amount paid to (or refund received from) the IRS. If
the current component is positive, the entry is:
DR CR
(current) income tax expense
Cash or income taxes payable
The firm will credit the current liability because it makes its tax accrual as of December 31st, but sends the
check a few weeks later. If the current component is negative, the entry is:
DR CR
cash or income tax refund receivable
(current) income tax expense
Negative current income tax expense is due to a Net Operating Loss (NOL), discussed below. Like in the positive
case, either cash or a current asset account can be in the entry.
The deferred component of income tax expense is the other side in the journal entry to deferred tax assets/liabilities.
Here are some possible cases.
(1) If deferred tax assets increase by 100 (DR) and deferred tax liabilities increase by 200 (CR), then deferred
income tax expense is positive (DR) 100. The entry is:
DR CR
(deferred) income tax expense 100
deferred tax assets 100
Deferred tax liabilities 100
(2) If deferred tax assets increase by 200 (DR) and deferred tax liabilities increase by 100 (CR), then deferred
income tax expense is negative (CR) 100. The entry is:
DR CR
deferred tax assets 200
Deferred tax liabilities 100
(deferred) income tax expense 100
(3) If deferred tax assets decrease by 100 (CR) and deferred tax liabilities decrease by 200 (DR), then deferred
income tax expense is negative (CR) 100. The entry is:
DR CR
Deferred tax liabilities 200
(deferred) income tax expense 100
deferred tax assets 100
(4) If deferred tax assets decrease by 200 (CR) and deferred tax liabilities decrease by 100 (DR), then deferred
income tax expense is positive (DR) 100. The entry is:
DR CR
(deferred) income tax expense 100
Deferred tax liabilities 100
deferred tax assets 200
(5) If deferred tax assets increase (DR) and deferred tax liabilities decrease (DR), then deferred tax expense
must be negative (CR). The entry is:
DR CR
Deferred tax liabilities
Deferred tax assets
(deferred) income tax expense
(6) If deferred tax assets decrease (CR) and deferred tax liabilities increase (CR), then deferred tax expense
must be positive (DR). The entry is:
DR CR
(deferred) income tax expense
Deferred tax liabilities
deferred tax assets
I have the shown the journal entries for the 2 components of income tax separately, but they can be combined into
one. For example, assume that the current component of income tax expense is a positive (DR) 300, and the deferred
component is as shown in entry #3, above. The combined entry is:
DR CR
Income tax expense 200
Deferred tax liabilities 200
Cash or taxes payable 300
Deferred tax assets 100
It is obvious from the entry that the current and deferred components of income tax expense are 300 and -100, respectively.
Note that income tax expense is like any other expense account under the accrual method in that the expense does
not necessarily equal the cash outflow. In this sense, deferred tax accounting is just another example of accrual
accounting.
Balance Sheet Method
The method to compute the components of income tax expense and deferred tax assets and liabilities is called the
balance sheet method. (1) Compute the current component of income tax expense (tax reporting), equal to current
taxable income x currently prevailing tax rate. This is always the first step, because it is independent of financial
reporting rules. (2) Compute the deferred component of income tax expense by calculating the (changes in the) deferred
tax asset and deferred tax liability accounts. It is important to know whether the timing differences are originating
or reversing. If they are originating, construct a schedule of all future revenues and expenses for book and tax
purposes. Multiply each future year's timing difference (between book vs. tax revenue and expense) by the tax rate
expected to be in effect at the time of future reversal. Then sum over all future years, to calculate the increase
in the deferred tax asset (DR) or liability (CR) balances. If they are reversing, the decrease in the deferred
tax asset (CR) or liability (DR) balance is the reversing amount x the tax rate used to create the balance originally.
(3) Compute total income tax expense as the sum of the 2 components. RCJ flowchart this procedure in Figure 12.5
(page 622) and show a detailed example on pages 641-647. It is called the balance sheet method because you back
into deferred (and thereby total) income tax expense via the changes in the B/S (deferred tax asset and liability)
accounts. Thus,
deferred tax liability (asset) = future taxable (deductible) amount due to timing difference x future tax rate
[or, future timing difference = deferred tax A or L ÷ tax rate], and
)deferred tax liability (asset) = )future taxable (deductible) amount x future tax rate
[or, )future timing difference = )deferred tax A or L ÷ tax rate].
Note that the B/S method absorbs the full effect of a tax rate change on net income in the year that the change
is enacted (even if the rate change will not go into effect right away). This is because the beginning of year
balances of deferred tax assets and liabilities are based on the old tax rate, while the end of year balances are
based on the new tax rate (when the differences reverse); thus, the change in the balances, which equals the deferred
tax expense, are affected right away. The effect on net income due to the rate change is a one-time, transitory
effect (unless rates keep changing. The impact of the rate change on NI depends on: 1. the change in the tax rate
2. whether the firm has a net deferred tax asset or liability balance 3. the magnitude of the balance. RCJ summarize
the tax journal entry procedure in Figure 12.8 (page 631).
Net Operating Losses (NOL's)
An NOL is negative taxable income. Book income may be either positive or negative, it doesn't matter. An NOL means
that current and/or deferred income tax expense is negative (CR). An NOL firm has two choices. It can carryback
the loss to offset past taxable income and get a refund of past taxes paid. The entry is:
DR CR
cash or tax refund receivable
(current) income tax expense
The maximum carryback period is 2 years (offset the earlier year first, as in FIFO); i.e, a firm must have had
positive taxable income in at least one of the past 2 years in order to carryback. Or, the firm can carryforward
the loss to offset future income (also FIFO) and thereby reduce the payment of future taxes, producing a deferred
tax asset. The entry is:
DR CR
deferred tax asset
(deferred) income tax expense
A firm can carryforward an NOL for up to 20 years. Thus, NOL carryforwards are another source of deferred tax assets,
in addition to the timing differences discussed above. Why would a firm choose to carryforward (other than not
being able to carryback because of 2 years of losses)? The "time value of money" incentive says to get
the cash now (carryback). But, if tax rates are expected to go up in the future, a dollar of deduction will become
worth more, so this incentive says to wait (carryforward).
Deferred Tax Asset Valuation Allowance
A deferred tax asset is a reduction in future cash outflow (taxes to be paid). But, the asset has value only if
the firm expects to pay taxes in the future. For example, an NOL carryforward is worthless if the firm does not
expect to have positive taxable income for the next 20 years. Since accounting is conservative, firms must reduce
the value of their deferred tax assets by a deferred tax asset valuation allowance. This is a contra-asset account
(CR balance on the B/S - just like accumulated depreciation or the allowance for uncollectible accounts) that reduces
the deferred tax asset to its expected realizable value. The easiest way to record the valuation allowance is to
record the deferred tax asset in the usual way (as if there were no valuation allowance) and then to make an additional
entry:
DR CR
(deferred) income tax expense
deferred tax asset valuation allowance
Note that increasing the allowance (CR) increases deferred income tax expense; decreasing the allowance does the
opposite. Increases in the valuation allowance are recorded by the above entry, and decreases in the allowance
are recorded by a reversal of the entry. Thus, changes in the allowance affect income tax expense, and are another
reason why the B/S method is superior to the I/S method. Although the need for an allowance is subjective, its
existence and magnitude reveals management's expectation of future earnings. Management can use changes in the
allowance to "manipulate" NI, by affecting income tax expense.
Permanent Differences - Effective Tax Rates
The importance of permanent differences is that they cause the effective income tax rate to differ from the statutory
(government) rate (I); non-deductible expenses raise the effective income tax rate, while non-taxable revenues
lower the effective income tax rate. To see this, write the effective income tax rate (ETR) as:
ETR = current tax expense + deferred tax expense
Taxable income + temp diffs - non-deductible expenses + non-taxable revenues
By definition, current tax expense = I = deferred tax expense
taxable income Temp diffs
Thus, I = current tax expense+deferred tax expense
taxable income + temp diffs
Note that in the absence of permanent differences, T equals the statutory tax rate. From the definitions for ETR
and I, non-deductible expenses lower the denominator of ETR, raising the ratio above I; non-taxable revenues raise
the denominator of ETR, lowering the ratio below I. RCJ give some examples of permanent differences in Table 12.2
on page 610. Additionally, the tax footnote disclosure (see below) contains a reconciliation between the effective
and the (federal) statutory tax rates; permanent differences can be a key component of this difference.
Financial Statement Disclosures
Total income tax expense is shown on the I/S, while the net current and net non-current deferred tax asset or liability
are shown on the B/S. The following additional information is disclosed in a footnote: (1) current and deferred
components of total income tax expense, (2) reconciliation between the federal statutory and effective tax rates,
and (3) components of deferred tax assets and liabilities (e.g., revenue and expense items that cause the deferred
tax assets and liabilities, such as depreciation, bad debts, installment sales, etc.), both at the end and at the
beginning of the year (remember that the net change is the other side of the entry for deferred tax expense).
An example of the required disclosure is in Exhibit 12.2 on pages 628-629, which shows the tax footnote for Amoco
Corp. Note the three parts of the disclosure. From part (1), you can deduce the tax journal entry, except that
you cannot determine whether the offset to deferred tax expense is deferred tax assets and/or liabilities (part
(3) enables you to do this). Note that the information in part (1) pertains only to Income From Continuing Operations
(because the "below the line" components are shown net of tax). From part (2), you can tell why the firm's
book income is taxed at a higher or lower rate than the statutory rate, which tells you about the firm's tax policy
(i.e., is the firm using the tax system effectively). Part (3) shows the beginning of year and end of year balances
in the components of the firm's deferred tax assets and liabilities. This data can be used for the tax journal
entry and to know what specific accounts cause the timing differences.
Large increases in deferred tax liabilities or decreases in deferred tax assets might require special scrutiny.
Such changes are "legitimate" if they are associated with increases in the underlying assets or liabilities,
such as PPE or A/R, which can be deduced from the SCF. Changes that can't be linked with underlying assets or liabilities
might indicate manipulation of NI, via changes in accounting estimates. For example, an increase in depreciable
life (for books) lowers book dep'n, increasing the excess of tax dep'n over book dep'n, increasing the deferred
tax liability.
Changes in deferred tax assets and liabilities can also be used to compute expenses and revenues on the firm's
tax return. As pointed out above, )future timing difference = )deferred tax A or L ÷ tax rate. Thus, the
)deferred tax A or L from the footnote can be used to compute the )future timing difference, which is the current
year's difference between book vs tax revenue or expense. This can then be added to or subtracted from the book
revenue or expense to compute the corresponding tax figure. RCJ (pg 637) show an example with depreciation.
Note that current federal tax expense=federal statutory tax rate x taxable income; or current federal tax expense
÷ federal statutory tax rate = taxable income. The ratio pre-tax book income/taxable income can be used
as a measure of accounting conservatism (i.e., earnings quality). Taxable income is a very conservative performance
measure (because firms try to minimize tax payments). The lower (higher) the ratio, the more conservative (aggressive)
is the firm's accounting. Using this ratio, one can then compare different companies at a point in time, or one
company over time.