Examine the income statements of Berkshire Hathaway Inc. for the years ended December 31, 2022, and 2021.

Berkshire Hathaway Inc.	2022	2021
Sales	$315,731	$276,094
Cost of Goods Sold	$177,432	$150,987
Gross Profit	$138,299	$125,107
Operating Expenses	$71,998	$67,543
Net Income	$42,521	$39,145

Requirements:

1. Calculate the gross profit margin for each year.
2. Calculate the operating profit margin for each year.
3. Compute the net profit margin for each year.
4. Discuss the financial performance of Berkshire Hathaway Inc. over the two-year period.