What is Simon Harrison's Total target value expressed as percentage of total target values for all Named Executive Officer?
{"Mark J. Barrenechea": {"Performance Share Units": 2815000, "Restricted Share Units": 1407500, "Stock Options": 1407500, "Total": 5630000}, "Madhu Ranganathan": {"Performance Share Units": 500000, "Restricted Share Units": 250000, "Stock Options": 250000, "Total": 1000000}, "Muhi Majzoub": {"Performance Share Units": 550000, "Restricted Share Units": 275000, "Stock Options": 275000, "Total": 1100000}, "Gordon A. Davies": {"Performance Share Units": 500000, "Restricted Share Units": 250000, "Stock Options": 250000, "Total": 1000000}, "Simon Harrison": {"Performance Share Units": 218750, "Restricted Share Units": 109375, "Stock Options": 109375, "Total": 437500}}
simon_harrison_total = df["Simon Harrison"]["Total"]
total_target_values = df["Mark J. Barrenechea"]["Total"] + df["Madhu Ranganathan"]["Total"] + df["Muhi Majzoub"]["Total"] + df["Madhu Ranganathan"]["Total"] + df["Simon Harrison"]["Total"]
answer = simon_harrison_total / total_target_values * 100.0