The table below shows a summarized statement for Tenet Inc., the healthcare system with hospitals in Dallas, El Paso and other major cities in Texas. Using the data from the table

1) calculate Operating Income for each year.

2) calculate Operating Margin for each year.

3) explain the trend in terms of operating income and operating margin.

	12/31/2021	12/31/2020	12/31/2019	12/31/2018
Total Revenue	19,485,000	17,640,000	18,479,000	18,313,000
Cost of Revenue	3,328,000	2,982,000	3,057,000	3,004,000
Gross Profit	16,157,000	14,658,000	15,422,000	15,309,000
Operating Expense	13,748,000	12,518,000	13,743,000	13,692,000