<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>1080 - Disclosure - ACCUMULATED OTHER COMPREHENSIVE LOSS</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

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&lt;p style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;&lt;b&gt;NOTE 8&amp;#8212;ACCUMULATED OTHER COMPREHENSIVE LOSS&lt;/b&gt;&lt;/font&gt;&lt;/p&gt;
&lt;p style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;&amp;#160;The Company's accumulated other comprehensive loss is related to the Scioto Downs defined benefit pension plan. A summary of the change in accumulated other comprehensive loss as of June&amp;#160;30, 2013 is as follows (in thousands):&lt;/font&gt;&lt;/p&gt;
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&lt;tr style="padding:0;"&gt;&lt;!-- TABLE COLUMN WIDTHS SET --&gt;
&lt;td style="FONT-FAMILY: times;" align="left"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;" width="12"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;" width="7" align="right"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;" width="34"&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;" width="12"&gt;&lt;/td&gt;&lt;!-- TABLE COLUMN WIDTHS END --&gt;&lt;/tr&gt;
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&lt;p style="TEXT-INDENT: -10pt; FONT-FAMILY: times; MARGIN-LEFT: 10pt;"&gt;&lt;font size="2"&gt;Balance as of December&amp;#160;31, 2012&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;" align="right"&gt;&lt;font size="2"&gt;$&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;" align="right"&gt;&lt;font size="2"&gt;(341&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;)&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
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&lt;td style="FONT-FAMILY: times;"&gt;
&lt;p style="TEXT-INDENT: -10pt; FONT-FAMILY: times; MARGIN-LEFT: 10pt;"&gt;&lt;font size="2"&gt;Other comprehensive loss before reclassifications&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;" align="right"&gt;&lt;font size="2"&gt;&amp;#8212;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
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&lt;td style="FONT-FAMILY: times;"&gt;
&lt;p style="TEXT-INDENT: -10pt; FONT-FAMILY: times; MARGIN-LEFT: 10pt;"&gt;&lt;font size="2"&gt;Amounts reclassified from accumulated other comprehensive loss(1)&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
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&lt;td style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;" align="right"&gt;&lt;font size="2"&gt;21&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="padding:0; FONT-SIZE: 1.5pt;" valign="top"&gt;
&lt;td style="FONT-FAMILY: times;" valign="bottom"&gt;&amp;#160;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;" valign="bottom"&gt;&amp;#160;&lt;/td&gt;
&lt;td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times;" valign="bottom" colspan="2" align="right"&gt;&amp;#160;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;" valign="bottom"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
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&lt;td style="FONT-FAMILY: times;"&gt;
&lt;p style="TEXT-INDENT: -10pt; FONT-FAMILY: times; MARGIN-LEFT: 10pt;"&gt;&lt;font size="2"&gt;Net current-period other comprehensive loss&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;" align="right"&gt;&lt;font size="2"&gt;21&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="padding:0; FONT-SIZE: 1.5pt;" valign="top"&gt;
&lt;td style="FONT-FAMILY: times;" valign="bottom"&gt;&amp;#160;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;" valign="bottom"&gt;&amp;#160;&lt;/td&gt;
&lt;td style="BORDER-BOTTOM: #000000 1pt solid; FONT-FAMILY: times;" valign="bottom" colspan="2" align="right"&gt;&amp;#160;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;" valign="bottom"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;
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&lt;td style="FONT-FAMILY: times;"&gt;
&lt;p style="TEXT-INDENT: -10pt; FONT-FAMILY: times; MARGIN-LEFT: 10pt;"&gt;&lt;font size="2"&gt;Balance as of June&amp;#160;30, 2013&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;&amp;#160;&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;" align="right"&gt;&lt;font size="2"&gt;$&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;" align="right"&gt;&lt;font size="2"&gt;(320&lt;/font&gt;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;)&lt;/font&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr style="padding:0; FONT-SIZE: 1.5pt;" valign="top"&gt;
&lt;td style="FONT-FAMILY: times;" valign="bottom"&gt;&amp;#160;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;" valign="bottom"&gt;&amp;#160;&lt;/td&gt;
&lt;td style="BORDER-BOTTOM: #000000 2.25pt double; FONT-FAMILY: times;" valign="bottom" colspan="2" align="right"&gt;&amp;#160;&lt;/td&gt;
&lt;td style="FONT-FAMILY: times;" valign="bottom"&gt;&amp;#160;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;&lt;/div&gt;
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&lt;div style="POSITION: relative; TEXT-ALIGN: left; PADDING-BOTTOM: 0pt; PADDING-LEFT: 0pt; PADDING-RIGHT: 0pt; MARGIN-LEFT: 15%; PADDING-TOP: 0pt;"&gt;
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&lt;dd style="FONT-FAMILY: times;"&gt;&lt;font size="2"&gt;Amounts are presented after income tax, including consideration of related valuation allowance. No net tax benefit was recognized in 2013.&lt;/font&gt;&lt;/dd&gt;&lt;/dl&gt;&lt;/div&gt;
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