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USD ($) / shares

USD ($)

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&lt;div&gt;

&lt;p style="text-indent: -0.2in; margin: 0in 0in 0pt 0.2in; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&lt;b&gt;4.&lt;/b&gt;&amp;nbsp;&amp;nbsp; &lt;b&gt;&lt;font style="font-family: 'Times New Roman','serif'; font-size: 10pt;" class="_mt"&gt;Leasing activity&lt;/font&gt;&lt;/b&gt;&lt;font style="font-family: 'Times New Roman','serif'; font-size: 10pt;" class="_mt"&gt; &lt;/font&gt;&lt;/p&gt;

&lt;p style="text-indent: -0.2in; margin: 0in 0in 0pt 0.2in; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&amp;nbsp;&lt;/p&gt;

&lt;p style="text-align: justify; text-indent: 0.2in; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;The Company leases space in its real estate facilities to tenants primarily under non-cancelable leases generally ranging from one to 10 years. Future minimum rental revenues excluding recovery of operating expenses as of March 31, 2011 under these leases are as follows (in thousands):&lt;/p&gt;

&lt;p style="text-align: justify; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&lt;font style="background: yellow;" class="_mt"&gt; &lt;/font&gt;&amp;nbsp;&lt;/p&gt;

&lt;table style="border-collapse: collapse; font-family: 'Calibri','sans-serif'; font-size: 11pt;" class="MsoNormalTable" border="0" cellspacing="0" cellpadding="0" width="97%"&gt;
&lt;tr&gt;&lt;td style="padding-bottom: 0in; padding-left: 2.35pt; width: 410.25pt; padding-right: 2.35pt; padding-top: 0in;" valign="top" width="547"&gt;

&lt;p style="line-height: 93%; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&amp;nbsp;&lt;/p&gt;

&lt;p style="line-height: 93%; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;2011 &lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-bottom: 0in; padding-left: 2.35pt; width: 48.25pt; padding-right: 2.35pt; padding-top: 0in;" valign="top" width="64"&gt;

&lt;p style="line-height: 93%; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&lt;font style="line-height: 93%;" class="_mt"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; $&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 163,702&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td style="padding-bottom: 0in; padding-left: 2.35pt; width: 410.25pt; padding-right: 2.35pt; padding-top: 0in;" valign="top" width="547"&gt;

&lt;p style="line-height: 93%; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&lt;font style="line-height: 93%;" class="_mt"&gt;2012 &lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-bottom: 0in; padding-left: 2.35pt; width: 48.25pt; padding-right: 2.35pt; padding-top: 0in;" valign="top" width="64"&gt;

&lt;p style="line-height: 93%; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&lt;font style="line-height: 93%;" class="_mt"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 176,985&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td style="padding-bottom: 0in; padding-left: 2.35pt; width: 410.25pt; padding-right: 2.35pt; padding-top: 0in;" valign="top" width="547"&gt;

&lt;p style="line-height: 93%; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&lt;font style="line-height: 93%;" class="_mt"&gt;2013 &lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-bottom: 0in; padding-left: 2.35pt; width: 48.25pt; padding-right: 2.35pt; padding-top: 0in;" valign="top" width="64"&gt;

&lt;p style="line-height: 93%; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&lt;font style="line-height: 93%;" class="_mt"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 122,808&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td style="padding-bottom: 0in; padding-left: 2.35pt; width: 410.25pt; padding-right: 2.35pt; padding-top: 0in;" valign="top" width="547"&gt;

&lt;p style="line-height: 93%; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&lt;font style="line-height: 93%;" class="_mt"&gt;2014 &lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-bottom: 0in; padding-left: 2.35pt; width: 48.25pt; padding-right: 2.35pt; padding-top: 0in;" valign="top" width="64"&gt;

&lt;p style="line-height: 93%; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&lt;font style="line-height: 93%;" class="_mt"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 78,888&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td style="padding-bottom: 0in; padding-left: 2.35pt; width: 410.25pt; padding-right: 2.35pt; padding-top: 0in;" valign="top" width="547"&gt;

&lt;p style="line-height: 93%; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&lt;font style="line-height: 93%;" class="_mt"&gt;2015 &lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-bottom: 0in; padding-left: 2.35pt; width: 48.25pt; padding-right: 2.35pt; padding-top: 0in;" valign="top" width="64"&gt;

&lt;p style="line-height: 93%; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&lt;font style="line-height: 93%;" class="_mt"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 51,152&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td style="padding-bottom: 0in; padding-left: 2.35pt; width: 410.25pt; padding-right: 2.35pt; padding-top: 0in;" valign="top" width="547"&gt;

&lt;p style="line-height: 93%; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&lt;font style="line-height: 93%;" class="_mt"&gt;Thereafter &lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-bottom: 0in; padding-left: 2.35pt; width: 48.25pt; padding-right: 2.35pt; padding-top: 0in;" valign="top" width="64"&gt;

&lt;p style="line-height: 93%; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&lt;font style="line-height: 93%;" class="_mt"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; &lt;u&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 81,150&lt;/u&gt;&lt;/font&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td style="padding-bottom: 0in; padding-left: 2.35pt; width: 410.25pt; padding-right: 2.35pt; padding-top: 0in;" valign="top" width="547"&gt;

&lt;p style="line-height: 93%; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&lt;font style="line-height: 93%;" class="_mt"&gt;Total &lt;/font&gt;&lt;/p&gt;&lt;/td&gt;
&lt;td style="padding-bottom: 0in; padding-left: 2.35pt; width: 48.25pt; padding-right: 2.35pt; padding-top: 0in;" valign="top" width="64"&gt;

&lt;p style="border-bottom: black 3px double; line-height: 93%; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&lt;font style="line-height: 93%;" class="_mt"&gt;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; $&amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp; 674,685 &lt;/font&gt;&lt;/p&gt;&lt;/td&gt;&lt;/tr&gt;&lt;/table&gt;

&lt;p style="margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&lt;font style="background: yellow;" class="_mt"&gt; &lt;/font&gt;&amp;nbsp;&lt;/p&gt;

&lt;p style="text-align: justify; text-indent: 0.2in; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;In addition to minimum rental payments, certain tenants reimburse the Company for their pro rata share of specified operating expenses. Such reimbursements amounted to $15.6 million and $14.4 million for the three months ended March 31, 2011 and 2010, respectively. These amounts are included as rental income in the accompanying consolidated statements of income.&lt;/p&gt;

&lt;p style="text-align: justify; margin: 0in 0in 0pt; font-family: 'Times New Roman','serif'; font-size: 10pt;" class="MsoNormal"&gt;&amp;nbsp;&lt;/p&gt;&lt;font style="font-family: 'Times New Roman','serif'; font-size: 10pt;" class="_mt"&gt;Leases accounting for 6.1% of total leased square footage are subject to termination options which include leases accounting for 2.9% of total leased square footage having termination options exercisable through December 31, 2011. In general, these leases provide for termination payments should the termination options be exercised. The above table is prepared assuming such options are not exercised.&lt;/font&gt;&lt;/div&gt; &lt;/div&gt;</NonNumbericText><NonNumericTextHeader>4.&amp;nbsp;&amp;nbsp; Leasing activity

&amp;nbsp;

The Company leases space in its real estate facilities to tenants primarily under non-cancelable leases generally</NonNumericTextHeader><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat><hasSegments>false</hasSegments><hasScenarios>false</hasScenarios></Cell></Cells><OriginalInstanceReportColumns /><Unit>Other</Unit><ElementDataType>us-types:textBlockItemType</ElementDataType><SimpleDataType>string</SimpleDataType><ElementDefenition>General description of lessee's leasing arrangements including: (1) The basis on which contingent rental payments are determined, (2) The existence and terms of renewal or purchase options and escalation clauses, (3) Restrictions imposed by lease arrangements, such as those concerning dividends, additional debt, and further leasing, (4) Rent holidays, rent concessions, or leasehold improvement incentives and unusual provisions or conditions.  Disclosure may also include the specific period used to amortize material leasehold improvements made at the inception of the lease or during the lease term. Additionally, for operating leases having initial or remaining noncancelable lease terms in excess of one year: (a) future minimum rental payments required as of the date of the latest balance sheet presented, in the aggregate and for each of the five succeeding fiscal years, (b) the total of minimum rentals to be received in the future under noncancelable subleases as of the date of the latest balance sheet presented, and (c) for all operating leases, rental expense for each period for which an income statement is presented, with separate amounts for minimum rentals, contingent rentals, and sublease rentals. Rental payments under leases with terms of a month or less that were not renewed need not be included.</ElementDefenition><ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 13
 -Paragraph 16
 -Subparagraph b, c, d

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