Exhibit A to Performance Share Unit Agreement

The Performance Share Units are granted under and governed by the terms and conditions of the Plan and this Performance Share Unit Agreement including Exhibit A. Additional provisions regarding your Performance Share Units and definitions of capitalized terms used and not defined in this Performance Share Unit Agreement can be found in the Plan.

Termination of Employment: (1) If your employment with the Company and its Affiliates is terminated prior to the third December 31 following the Grant Date for any reason other than death, Disability or Retirement (based solely on clause (iii) of the definition of such term in the Plan), then you will forfeit any Performance Share Units as of the date your employment is terminated. (2) If you cease to be employed by the Company and its Affiliates prior to the third December 31 following the Grant Date by reason of death, Disability or Retirement (based solely on clause (iii) of the definition of such term in the Plan), then you will receive a portion of the number of Performance Share Units that you would have received had you not ceased to be employed by the Company and its Affiliates, which portion will be equal to such number of Performance Share Units multiplied by a fraction the numerator of which is the number of Months (counting a partial Month as a full Month) from the Grant Date until the date your employment is terminated by reason of death, Disability or Retirement (based solely on clause (iii) of the definition of such term in the Plan), and the denominator of which is the number of Months from the Grant Date to the third December 31 following the Grant Date, and you will forfeit any remaining Performance Share Units. For purposes of this Agreement, a “Month” shall mean the period that begins on the first calendar day after the Grant Date or the applicable anniversary of the Grant Date that occurs in each calendar month, and ends on the anniversary of the Grant Date that occurs in the following calendar month.

Voting Rights and Dividends: You are not entitled to exercise any voting rights with respect to the Common Stock of HDI underlying your Performance Share Units. You will not receive cash payments relating to any dividends and other distributions paid with respect to the Shares underlying your Performance Share Units at the time of the payment date of the dividend or other distribution. If, however, any dividends or distributions with respect to the Common Stock of HDI underlying your Performance Share Units are paid in Shares rather than cash, you will be credited with additional Performance Share Units equal to the number of shares that you would have received had your Performance Share Units been actual Shares, and such Performance Share Units will be subject to the same risk of forfeiture and other terms of this Performance Share Unit Agreement as are the Performance Share Units that are granted contemporaneously with this Performance Share Unit Agreement. Amounts credited to you in the form of additional Performance Share Units will be settled (if vested) at the same time as the Performance Share Units with respect to which they were credited. Further, at the time Performance Share Units are settled, you will receive a dividend equivalent cash payment in respect of any dividends and other distributions paid in cash with respect to Shares for which the record date is on or after the Grant Date and before the settlement date which payment will be in an amount equal to the product of the number of Shares in respect of which payment will be made to you on settlement of your Performance Share Units and the total amount of dividends and other distributions paid in cash with respect to a Share during such period.

Settlement: Your Performance Share Units will be settled by delivery to you of a cash payment in respect of Shares on a one-for-one basis, with payment for one Share being made for each Performance Share Unit that you earn. As soon as practicable following the date on which the Performance Share Units are earned, the Company will make a cash payment to you equal to the product obtained by multiplying the Fair Market Value of a Share on the date your Performance Share Units are earned by the number of Performance Share Units that you have earned, plus any dividend equivalent amount due, which payment will be made in your local currency using the spot rate on the date your Performance Share Units are earned, less applicable withholding.