Adjusted segment operating profit was $1.4 billion, 23% higher than the fourth quarter of 2020.
Our trailing four-quarter adjusted EBITDA was $4.9 billion, $1.25 billion more than a year ago.
And our trailing four-quarter average adjusted ROIC was 10%, meeting our objectives.
For the full year, our adjusted earnings per share was $5.19, also a record.
And full year adjusted segment operating profit was $4.8 billion.
AS&O delivered full year 2021 OP of $2.8 billion, with each subsegment performing at or near historic highs.
Carbohydrate solutions executed phenomenally well to deliver full year operating profits of $1.3 billion.
And the team is continuing the evolution of carbohydrate solutions from the sale of our Peoria dry mill and the announcement of the sustainable aviation fuel MOU; to our agreement with LG Chem and the continued growth of our exciting biosolutions platform, which delivered new revenue wins with an annualized run rate of almost $100 million; to the project we announced earlier this month to further decarbonize our operations by connecting two other major processing facilities; to our vacate of carbon capture and storage capabilities.
The nutrition team once again delivered industry-leading revenue and OP growth, with full year revenues up 16% and full year OP of $691 million, representing a 20% year-over-year increase.
We are confident in our plan [Audio gap] which is why we are pleased to announce an 8% increase in our quarterly dividend to $0.40 per share.
We are proud of our record of 90 uninterrupted years of dividends and more than 40 years of consecutive annual dividend increases, and we are pleased to continue to follow through on our commitment to shareholder value creation.
Lower results in EMEA versus a very strong fourth quarter of 2020 and approximately $250 million in net negative timing impacts versus negative $125 million in the prior-year quarter drove overall results lower year over year.
The nutrition business closed out a year of consistent and strong growth, with fourth quarter revenues 19% higher year over year, 21% on a constant currency basis, with 26% higher profits year over year, and sustained strong EBITDA margins.
Human Nutrition had a great fourth quarter, with revenue growth of 21% on a constant currency basis and substantially higher profits.
Animal nutrition revenue was up 21% on a constant currency basis, and operating profit was much higher year over year, driven primarily by continued strength in amino acids.
Now looking ahead, we expect nutrition to continue to grow operating profits at a 15%-plus rate for calendar year 2022, with the first quarter similar to the first quarter of 2021 with continued revenue growth offset by some higher costs upfront in the year and the absence of the onetime benefits we saw in the first quarter of the prior year.
Although for the first quarter, we expect a loss of about $25 million due to insurance settlements currently planned.
In the corporate lines, unallocated corporate costs of $276 million were lower year over year due primarily to increased variable performance-related compensation expense accruals in the prior year, partially offset by higher IT offering in project-related costs and transfers of costs from business segments into centralized centers of excellence in supply chain and operations.
We anticipate calendar year 2022 total corporate costs, including net interest, corporate unallocated, and other corporate, to be in line with the $1.2 billion area, consistent with what I discussed at Global Investor Day with net interest roughly similar, corporate unallocated a bit higher, and corporate other a bit lower.
The effective tax rate for the fourth quarter of 2021 was approximately 21%, compared to 8% in the prior year.
The calendar year 2021 effective tax rate was approximately 17%, up from 5% in 2020.
Looking ahead, we're expecting full year 2022 effective tax rate to be in the range of 16 to 19%.
Our balance sheet remains solid, with a net debt-to-total capital ratio of about 28% and available liquidity of about $9 billion.
And as we discussed at Global Investor Day, we believe that increasing demand for meal as well as vegetable oil as a feedstock for renewable green diesel should continue to support the positive environment this year, with our soy crush margins in the range of 45 to $55 per metric ton.
With this in mind, we're assuming higher ADM ethanol volumes and EBITDA margins to average $0.15 to $0.25 for the calendar year.
With these dynamics, we expect 15-plus percent OP growth in 2022, revenue growth above 10%, and EBITDA margins above 20% in human nutrition and high single digits in animal nutrition, consistent with targets we set out at our Global Investor Day.
Put it all together, and we're optimistic for another very strong performance in 2022 as we progress toward our strategic plans next earnings milestones of six to $7 per share.

Summary:
For the full year, our adjusted earnings per share was $5.19, also a record.
We are confident in our plan [Audio gap] which is why we are pleased to announce an 8% increase in our quarterly dividend to $0.40 per share.
The effective tax rate for the fourth quarter of 2021 was approximately 21%, compared to 8% in the prior year.