Under "Federal Non-Refundable Tax Credits", the "Personal Amount" for my wife (when doing joint return) is 50% higher than mine. Why? What is this based on?

The amount is determined according to the income you had. As per the Canada Revenue Agency (CRA) If your net income at line 23600 of your return is $165,430 or less, enter $15,000 on line 30000. If your net income is $235,675 or more, enter $13,520. Otherwise, complete the calculation using the Federal Worksheet to determine how much to claim on line 30000.

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