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   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt"&gt;&lt;u&gt;&lt;b&gt;NOTE 9. SHARE-BASED COMPENSATION PLANS&lt;/b&gt;&lt;/u&gt;
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   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt"&gt;&lt;b&gt;RESTRICTED STOCK UNITS AND PERFORMANCE SHARES&lt;/b&gt;
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   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt"&gt;&lt;b&gt;Restricted Stock Units&lt;/b&gt;
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   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt"&gt;In May&amp;#160;2010, the Compensation Committee of the UniSource Energy Board of Directors granted 15,620
   restricted stock units to non-employee directors at a grant date fair value of $31.69 per share.
   The restricted stock units vest in one year or immediately upon death, disability, or retirement.
   Compensation expense equal to the fair market value on the grant date is recognized over the
   vesting period. Fully vested but undistributed stock unit awards accrue dividend equivalent stock
   units based on the fair market value of common shares on the date the dividend is paid. In the
   January following the year the person is no longer a Director, Common Stock shares will be issued
   for the vested stock units.
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   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt"&gt;&lt;b&gt;Performance Shares&lt;/b&gt;
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   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt"&gt;In February&amp;#160;2010, the Compensation Committee of the UniSource Energy Board of Directors granted
   93,720 performance share awards (targeted shares) to Officers. 50% of the performance share awards
   had a grant date fair value, based on a Monte Carlo simulation, of $31.26 and will be paid out in
   shares of UniSource Energy Common Stock based on targeted, cumulative UniSource Energy Total
   Shareholder Return during the performance period of January&amp;#160;1, 2010 through December&amp;#160;31, 2012,
   compared to the Total Shareholder Return over the same period of an industry or peer group. The
   remaining 50% had a grant date fair value of $30.52 and will be paid out in shares of UniSource
   Energy Common Stock based on cumulative net income for the 3-year period ended December&amp;#160;31, 2012.
   The performance shares vest based on goal attainment upon completion of the performance period; any
   unearned awards are forfeited. Performance shares are eligible for dividend equivalents during the
   performance period.
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   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt"&gt;&lt;b&gt;SHARE-BASED COMPENSATION EXPENSE&lt;/b&gt;
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   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt"&gt;UniSource Energy and TEP recorded share-based compensation expense, net of amounts capitalized of
   less than $1&amp;#160;million, for each of the three months ended June&amp;#160;30, 2010 and 2009 and approximately
   $1&amp;#160;million for each of the six months ended June&amp;#160;30, 2010 and 2009.
   &lt;/div&gt;
   &lt;div align="left" style="font-size: 10pt; margin-top: 10pt"&gt;At June&amp;#160;30, 2010, the total unrecognized compensation cost related to non-vested share-based
   compensation was $4&amp;#160;million, which will be recorded as compensation expense over the remaining
   vesting periods through December&amp;#160;2012. The total number of shares awarded but not yet issued,
   including target performance based shares, under the share-based compensation plans at June&amp;#160;30,
   2010, was 1&amp;#160;million.
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      <ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 123R
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher AICPA
 -Name Statement of Position (SOP)
 -Number 93-6
 -Paragraph 53

Reference 3: http://www.xbrl.org/2003/role/presentationRef
 -Publisher SEC
 -Name Staff Accounting Bulletin (SAB)
 -Number Topic 14

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