What was the revenue growth rate for NATI's aerospace, defense, and government business in 2021
n and simulation with test.
And starting in 2022, we have made the decision to shift our single-seat software licenses to subscription, which will lead to more recurring revenue and better predictability in our business. Second, we focus to capitalize on secular trends by targeting system-level offerings to accelerate our growth. We targeted these offerings at 5G and wireless, electrification and autonomy, and new space applications. We restructured our sales force to increase direct engagement with top accounts in these domains.
And today, these applications and our focus accounts are growing significantly faster than the company and driving our overall growth. Third, we streamlined our business to create a more efficient engagement with customers and to drive scale and leverage in our broad-based business. We invested for multiple years in ni.com, and these investments showed strong return with online order growth up 44% in 2021. We shifted our Tier 3 customers to utilize global distribution partners, and the results from this shift exceeded our expectations in 2021.
Next, we focus on inorganic opportunities to accelerate our growth strategy. Last quarter, we announced two acquisitions in the high-growth application of electric vehicles, which we expect will add approximately 4% of revenue in 2022. NH Research delivered to plan in Q4, and we are targeting to close on the EV business of Heinzinger in late Q1 2022. I have high expectations for our multiyear growth in this industry focused on the large EV and ADAS investments of our customers.
We will continue to prioritize inorganic investments that strategically align to our business in order to accelerate growth. And lastly, we delivered on our commitment to drive efficiency across our cost structure. We better aligned our people to the critical needs of our growth strategy with headcount down 3% year over year in 2021 and a plan to remain approximately flat in headcount in 2022 in a year of expected strong revenue growth. And as I've said, we expect earnings to outpace revenue for the foreseeable future.
The effect of these changes brings increased confidence in our business as we enter 2022. We're in a position of strength with strong demand, record backlog, and disciplined expense management. So our expectation is to now meet or exceed our previous 2023 financial model in 2022, a full year ahead of schedule. As I said last quarter, we expect to deliver 16% to 18% revenue growth year over year in 2022, and we exceed our financial target of 20% non-GAAP operating margin.
Now onto our industry results for the full year 2021. The areas of intentional focus are delivering to our expectations. I believe this is a proof point that we are focused on the right areas to accelerate growth. We expect double-digit growth across all of our business units in 2022.
Semiconductor and electronics revenue was $394 million, up 21% year over year. We saw continued strength in our focus area of 5G and wireless communication, which represents more than 50% of revenue for this business, and we continue to see success in new offerings for automated labs in this space. Transportation revenue was $212 million, up 27% year over year. While this business previously correlated primarily to automotive production rates, our shift in focus to EV and ADAS where our customers are making significant investments, has shifted the trajectory of this business.
We expect by the end of 2022, these fast-growing applications will represent more than 50% of the revenue in transportation. Aerospace, defense, and government revenue was $370 million, up 8% year over year. This business remains a steady and profitable growth engine delivering year-over-year growth in both 2020 and 2021, led by strength in defense applications and new space investments. And our portfolio business, which represents the majority of our broad-based customers, achieved revenue of $496 million, up 10%.
In addition to the favorable macro, our focus on optimizing the channel and better positioning our offerings to these broad customers ha
n and simulation with test.
And starting in 2022, we have made the decision to shift our single-seat software licenses to subscription, which will lead to more recurring revenue and better predictability in our business. Second, we focus to capitalize on secular trends by targeting system-level offerings to accelerate our growth. We targeted these offerings at 5G and wireless, electrification and autonomy, and new space applications. We restructured our sales force to increase direct engagement with top accounts in these domains.
And today, these applications and our focus accounts are growing significantly faster than the company and driving our overall growth. Third, we streamlined our business to create a more efficient engagement with customers and to drive scale and leverage in our broad-based business. We invested for multiple years in ni.com, and these investments showed strong return with online order growth up 44% in 2021. We shifted our Tier 3 customers to utilize global distribution partners, and the results from this shift exceeded our expectations in 2021.
Next, we focus on inorganic opportunities to accelerate our growth strategy. Last quarter, we announced two acquisitions in the high-growth application of electric vehicles, which we expect will add approximately 4% of revenue in 2022. NH Research delivered to plan in Q4, and we are targeting to close on the EV business of Heinzinger in late Q1 2022. I have high expectations for our multiyear growth in this industry focused on the large EV and ADAS investments of our customers.
We will continue to prioritize inorganic investments that strategically align to our business in order to accelerate growth. And lastly, we delivered on our commitment to drive efficiency across our cost structure. We better aligned our people to the critical needs of our growth strategy with headcount down 3% year over year in 2021 and a plan to remain approximately flat in headcount in 2022 in a year of expected strong revenue growth. And as I've said, we expect earnings to outpace revenue for the foreseeable future.
 The effect of these changes brings increased confidence in our business as we enter 2022. We're in a position of strength with strong demand, record backlog, and disciplined expense management. So our expectation is to now meet or exceed our previous 2023 financial model in 2022, a full year ahead of schedule. As I said last quarter, we expect to deliver 16% to 18% revenue growth year over year in 2022, and we exceed our financial target of 20% non-GAAP operating margin.
Now onto our industry results for the full year 2021. The areas of intentional focus are delivering to our expectations. I believe this is a proof point that we are focused on the right areas to accelerate growth. We expect double-digit growth across all of our business units in 2022.
Semiconductor and electronics revenue was $394 million, up 21% year over year. We saw continued strength in our focus area of 5G and wireless communication, which represents more than 50% of revenue for this business, and we continue to see success in new offerings for automated labs in this space. Transportation revenue was $212 million, up 27% year over year. While this business previously correlated primarily to automotive production rates, our shift in focus to EV and ADAS where our customers are making significant investments, has shifted the trajectory of this business.
We expect by the end of 2022, these fast-growing applications will represent more than 50% of the revenue in transportation. Aerospace, defense, and government revenue was $370 million, up 8% year over year. This business remains a steady and profitable growth engine delivering year-over-year growth in both 2020 and 2021, led by strength in defense applications and new space investments. And our portfolio business, which represents the majority of our broad-based customers, achieved revenue of $496 million, up 10%.
In addition to the favorable macro, our focus on optimizing the channel and better positioning our offerings to these broad customers ha