Sell yourself like you sell the product
A sales cover letter is a pitch, and the hiring manager is the buyer. Open with your strongest proof - target attainment, revenue closed or a big win - and keep the focus on what you'll deliver for them.
Give your target alongside your attainment. '132% of a ₹1.8 crore target' paints a clear picture of both your results and the size of business you're used to.