I work in management consulting and lately had my yearly review with my boss with the intent to renegotiate my salary and yearly bonus. As usual I don't negotiate a lot because my boss is very generous. Our company's bonus calculations are complex, involving several performance indicators, sales incentives, and so on. Since I am interested in how the figures evolved, my boss always gives me a copy of the calculation sheet for transparency reasons.
The day after the review, when I went over the details, I found a minor mistake in it. The salary used in the calculation is lower than my actual salary and the result is that the yearly bonus is actually 5% (€50) lower than what it should be. Despite the overall impact being small, I care now that I know about it (I like things to be correct). At the same time this bonus is still more than I expected and I'm happy with it.
Our relationship is very open and transparent. Should I politely point my boss to that possible mistake or would that be ungrateful/rude?