HighTech Solutions Ltd. reports the following financial results for the years ended December 31, 2021, 2020, and 2019.

Description	2021	2020	2019
Revenue	$8,000,000	$7,500,000	$7,000,000
Cost of Goods Sold	$4,800,000	$4,500,000	$4,200,000
Gross Profit	$3,200,000	$3,000,000	$2,800,000
Research and Development	$1,200,000	$1,125,000	$1,050,000
Selling and Administrative	$800,000	$750,000	$700,000
Total Operating Expenses	$2,000,000	$1,875,000	$1,750,000
Operating Income	$1,200,000	$1,125,000	$1,050,000
Other Income	$160,000	$150,000	$140,000
Earnings Before Tax	$1,360,000	$1,275,000	$1,190,000
Tax Expense	$272,000	$255,000	$238,000
Net Income	$1,088,000	$1,020,000	$952,000

Requirements:

1. Prepare a common-size income statement for each year.
2. Calculate the R&D Expense Ratio for each year.
3. Determine the SG&A Expense Ratio for each year.
4. Analyze the trend in operating efficiency over the three years.