Fashion Forward Inc. is a clothing retailer. Below are the financial data for the last three years.

Description	2021	2020	2019
Net Sales	$3,500,000	$3,200,000	$2,800,000
Cost of Goods Sold	$2,100,000	$1,920,000	$1,680,000
Gross Profit	$1,400,000	$1,280,000	$1,120,000
Operating Expenses	$700,000	$640,000	$560,000
Operating Income	$700,000	$640,000	$560,000
Interest Expense	$140,000	$128,000	$112,000
Earnings Before Tax	$560,000	$512,000	$448,000
Income Tax	$112,000	$102,400	$89,600
Net Income	$448,000	$409,600	$358,400

Requirements:

1. Calculate the Gross Profit Percentage for each year.
2. Determine the Operating Margin for each year.
3. Compute the Net Profit Margin for each year.
4. Discuss the trend in operating performance over the three years.