<?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>125 - Disclosure - Basis of presentation (Tables)</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="MARGIN-TOP: 6px; MARGIN-BOTTOM: 0px"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;Provisions for depreciation
are computed for financial reporting purposes using the
straight-line method over the estimated useful life of the related
asset and for leasehold improvements over the lesser of the
estimated useful life of the related asset or the term of the
related lease as follows:&lt;/font&gt;&lt;/p&gt;
&lt;p style="MARGIN-TOP: 0px; MARGIN-BOTTOM: 0px; FONT-SIZE: 12px"&gt;
&amp;#xA0;&lt;/p&gt;
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&lt;tr&gt;
&lt;td width="51%"&gt;&lt;/td&gt;
&lt;td valign="bottom" width="2%"&gt;&lt;/td&gt;
&lt;td width="47%"&gt;&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;
&lt;td valign="top"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;Land and land improvements&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font size="1"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;Remaining term of Chinese land use right&lt;/font&gt;&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;
&lt;td valign="top"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;Building and improvements&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font size="1"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;5 to 40 years or remaining term of leasehold&lt;/font&gt;&lt;/td&gt;
&lt;/tr&gt;
&lt;tr&gt;
&lt;td valign="top"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;Machinery, equipment, furniture, and fixtures&lt;/font&gt;&lt;/td&gt;
&lt;td valign="bottom"&gt;&lt;font size="1"&gt;&amp;#xA0;&amp;#xA0;&lt;/font&gt;&lt;/td&gt;
&lt;td valign="top"&gt;&lt;font style="FONT-FAMILY: Times New Roman" size="2"&gt;3 to 10 years&lt;/font&gt;&lt;/td&gt;
&lt;/tr&gt;
&lt;/table&gt;
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