During 2021, our team delivered for all stakeholders by, first of all, achieving positive year-over-year identicals, without fuel, against very strong identicals last year and a two-year stack of 14.3%.
Also by connecting with customers through expanding our seamless ecosystem and remarkable, consistent delivery of full fresh and friendly customer experience for everyone, plus investing more than ever before in our associates to raise our average hourly rate to $17 and our average hourly rate to over $22 when you include compensation and benefits as well.
We balance all of these investments by achieving cost savings of greater than $1 billion for the fourth consecutive year, and alternative profits contributed an incremental $150 million of operating profit as well.
We remain confident in our growth model and our ability to deliver total shareholder return of 8% to 11% over time.
1 retailer in many exciting areas, such as specialty cheese, sushi, and floral.
As the world's largest florist, we sold over 76 million floral stems for Valentine's Day alone.
Our brands continue to resonate strongly with customers and maintains a culture of innovation, launching over 660 new items during the year.
We accelerated Home Chef's incredible milestone of becoming a billion-dollar brand, our fourth greater-than-$1 billion brand, which is pretty special.
Kroger is focused on delivering a seamless experience that requires 0 compromise by customers, and I think that's a really important point, 0 compromise required by customers.
Yael will go into a lot more detail tomorrow on what 0 compromise means for our customers at our business update.
During the quarter, we saw new seamless pickup and delivery to household acquisitions increased 25% compared to the third quarter.
As part of our Zero Hunger | Zero Waste social and environmental impact plan, last year, Kroger donated 499 million meals, that's right, 499 million meals, to feed hungry families across America.
And we continue to make progress toward our goal of 0 waste.
As part of our commitments to helping people live healthier lives, we've administrated almost 11 million doses of the COVID-19 vaccine through Kroger Health.
For our more than 450,000 associates, we strive to create a culture of opportunity, and we take seriously our role as a leading employer in the United States.
Last year alone, we provided more than $5 million to support associates through unexpected hardships through our Helping Hands Fund.
This includes providing critical funds for disaster relief for nearly 1,300 associates.
These investments were balanced with over $1 billion in cost savings and $150 million of incremental operating profit from alternative profit streams.
We delivered adjusted earnings per share of $3.68 per diluted share, up 6% compared to last year.
Identical sales, excluding fuel, were positive 0.2% and digital sales on a two-year stacked basis grew by 113%.
Our adjusted FIFO operating profit was $4.3 billion, up 6% over 2020.
Gross margin was 22% of sales for 2021.
The FIFO gross margin rate, excluding fuel, decreased 43 basis points compared to the same period last year.
The OG&A rate decreased 61 basis points, excluding fuel and adjustment items, reflecting a reduction in COVID-related costs and cost-saving initiatives, partially offset by significant investments in our associates.
Adjusted earnings per share was $0.91 for the quarter, up 12% compared to the same quarter last year.
Kroger reported identical sales without fuel of 4%, our strongest quarter of the year, with fresh departments leading the way.
Kroger's FIFO gross margin rate, excluding fuel, increased 3 basis points compared to the same period last year.
The OG&A rate, excluding fuel and adjustment items, increased 7 basis points.
The LIFO charge for the fourth quarter was $20 million, compared to an $84 million credit in the same period last year, and represented an $0.11 headwind to earnings per share in the quarter.
Our investment in fuel rewards, which is reflected in our supermarket gross margin, also helps customers stretch their dollars further and allowed us to achieve gallon growth of 5% in the fourth quarter, outpacing market growth.
The average retail price of fuel was $3.30 this quarter versus $2.20 in the same quarter last year.
Our cents per gallon fuel margin was $0.44, compared to $0.33 in the same quarter in 2020.
Kroger's net total debt-to-adjusted EBITDA ratio is now 1.63, compared to our target range of 2.3 to 2.5.
In total, Kroger returned $2.2 billion to investors via a combination of share repurchases and dividends.
Kroger has invested an incremental $1.2 billion in associate wages and training over the last four years.
In addition, we have committed to invest over $1.8 billion during the same time period to help address underfunding and better secure pensions for tens of thousands of associates.
Wage, healthcare, and pensions are included in all of the more than 350 collective bargaining agreements that cover approximately 66% of our associates.
During the fourth quarter, we ratified new labor agreements with the UFCW for associates in Fred Meyer, King Soopers, and our Michigan division, covering more than 20,500 associates.
We have shared previously that we expect to emerge from the pandemic stronger, and our guidance for 2022 creates a new baseline for FIFO net operating profit that is some $900 million higher than the midpoint of our TSR model would have projected when we announced it in 2019.
We expect these investments and the impact of cycling COVID-19 vaccine revenue will be fully offset by tailwinds in our model and allow us to grow adjusted net earnings per diluted share to between $3.75 and $3.85.
The tailwinds in our 2022 plan includes sales leverage from growing identical sales without fuel between 2% and 3%.
We also expect to deliver cost savings of $1 billion, incremental alternative profit growth largely in line with 2021, and underlying improvement in Kroger Health profitability, excluding vaccine income.
In terms of quarterly cadence for identical sales of our fuel and earnings per share growth, we expect identical sales without fuel in quarter 1 and quarter 2 will be above the midpoint of our 2% to 3% range as we expect heightened inflation will continue in the first half of the year.
Regarding adjusted EPS, we would expect quarter 1 to be above the annual growth rate range of 2% to 5%, quarter 2 to be below the range and the second half of the year to be within the range.
At the same time, we expect to generate free cash flow of between $2 billion and $2.2 billion.
And finally, we are looking forward to spending more time with you at our business update tomorrow when you will hear from key members of our leadership team about our strategic priorities and our path to deliver total shareholder returns of 8% to 11% over time.
And when we do this, we have a clear path to delivering on our commitment of 8% to 11% total shareholder returns over time for our shareholders.
As Rob shared at the top of the call, we would like to focus all questions on our quarter 4 and full year 2021 results, as well as 2022 guidance.

Summary:
Adjusted earnings per share was $0.91 for the quarter, up 12% compared to the same quarter last year.
We expect these investments and the impact of cycling COVID-19 vaccine revenue will be fully offset by tailwinds in our model and allow us to grow adjusted net earnings per diluted share to between $3.75 and $3.85.