Using the following financial data for Pfizer Inc. for the years 2018, 2019, and 2020, perform the financial analysis:

	2018	2019	2020
Revenue	$53,647	$51,750	$48,650
Cost of Goods Sold	$16,250	$15,900	$14,750
Gross Profit	$37,397	$35,850	$33,900
Operating Expenses	$21,550	$22,250	$23,000
Operating Income	$15,847	$13,600	$10,900
Net Income	$11,153	$10,000	$8,250

	2018	2019	2020
Total Assets	$160,230	$156,840	$152,365
Total Liabilities	$92,450	$91,250	$89,800
Shareholders' Equity	$67,780	$65,590	$62,565

Requirements:

1. Calculate the gross profit margin for each year.
2. Determine the operating profit margin for each year.
3. Calculate the net profit margin for each year.
4. Compute the return on assets (ROA) for each year.
5. Compute the return on equity (ROE) for each year.
6. Discuss the financial performance trend of Pfizer Inc.