INCOME TAXES

A reconciliation of the U.S. federal statutory income tax rate to our effective income tax rate is as follows:



	For the Three Months Ended June 30,				For the Six Months Ended June 30,
	2018		2017		2018		2017
U.S. federal statutory income tax rate	21.0	%	35.0	%	21.0	%	35.0	%
State income taxes	2.5	%	1.8	%	2.5	%	1.8	%
Excess tax benefits from stock-based compensation plans	—	%	—	%	-0.1	%	-0.8	%
Other	0.2	%	0.1	%	0.4	%	0.1	%
Effective income tax rate	23.7	%	36.9	%	23.8	%	36.1	%

The decrease in our effective income tax rate for the three and six months ended June 30, 2018 is primarily due to the enactment of the 2017 Tax Act, which lowered our federal statutory income tax rate from 35% to 21%. Based on currently enacted federal and state statutory income tax rates, we believe our long-term effective income tax rate will decrease from 37% in past years to approximately 23% in 2018 and future years.

The differences between the U.S. federal statutory income tax rate and our effective income tax rate are primarily due to state income taxes and excess tax benefits from stock-based compensation plans. We receive a tax deduction upon the vesting of restricted stock and the conversion of restricted stock units to common stock based on the fair value of the shares. The amount that this tax deduction differs from the grant-date fair value that was recognized as stock-based compensation expense is referred to as an excess tax benefit or deficiency.

Valuation allowance

As a result of the enactment of the 2017 Tax Act, we established a valuation allowance related to the executive compensation provisions of the law that limit a public entity's ability to deduct compensation for covered employees in excess of $1.0 million for years after December 31, 2017, regardless of the nature of those payments. In prior years, qualifying performance-based compensation was excluded from the $1.0 million limitation. Qualifying performance-based compensation paid in 2018 or later under written binding contracts that were in effect on November 2, 2017 will remain excluded from the $1.0 million limitation unless such contracts are subsequently materially modified. Due to the lack of guidance for the new executive compensation provisions, we have made a reasonable estimate related to stock-based compensation, in accordance with ASU 2018-05. As of June 30, 2018 and December 31, 2017, the valuation allowance was $6.1 million and $5.5 million, respectively. This estimate may be refined in future periods as further information becomes available.

Valuation of Loans receivable

The 2017 Tax Act revises the rules associated with the timing of the recognition of income for federal income tax purposes. The 2017 Tax Act requires an accrual method taxpayer to recognize income no later than the taxable year in which such income is recognized as revenue in the financial statements, if the taxpayer is subject to the all events test—a requirement that all the events have occurred that fix the right to receive income, and that the amount can be determined with reasonable accuracy. The Senate Finance Committee intended that the new financial statement conformity requirement not be construed as preventing the use of special methods of accounting provided elsewhere in the Internal Revenue Code. It is unclear if our income recognition method related to the valuation of loans receivable is an allowable exception under the 2017 Tax Act. As we were not able to determine a reasonable estimate based on current guidance, we will continue to apply ASC Topic 740, Income Taxes, in accordance with ASU 2018-05 and based on the provisions of the tax laws that were in effect immediately prior to the 2017 Tax Act being enacted. This treatment may change in future periods as further information becomes available.