Additionally, we are helping to move relief to Ukraine, and we have provided more than $1.5 million in humanitarian aid.
Execution of our strategies resulted in substantially higher operating income for the quarter as Team FedEx delivered yet another outstanding peak season.
In January alone, the absentee rate of our crew due to omicron was over 15%, which caused significant flight disruptions.
We estimate the effect of omicron-driven volume softness in our Q3 results was approximately $350 million.
Even with these challenges, FedEx Express delivered strong adjusted operating income growth of 27% year over year.
Speaking of the Express team, we announced that after nearly 40 years of distinguished service, Don Colleran, president and CEO of FedEx Express, will retire later this year and named Richard Smith, current executive vice president of global support and regional president of Americas at FedEx Express, as a successor.
FedEx Freight once again delivered strong results with third quarter operating income nearly tripling year over year, driven by a continued focus on revenue quality.
We estimate the total impact of approximately $210 million at ground in the third quarter, which is significantly lower than what we saw in Q1 and Q2 as we have seen substantial improvement in labor availability post peak.
For example, FedEx Freight trucks have traveled more than 7 million miles while operating on behalf of FedEx Ground this fiscal year.
FedEx Freight has also provided FedEx Ground with intermodal containers, which have already been dispatched more than 36,000 times.
For example, during Cyber Week, this technology helped keep 1.9 million ground economy packages out of constrained sorts.
U.S. GDP is now expected to increase 3.4% in calendar year 2022, revised down from 3.7%, and our outlook is 2.3% in calendar year 2023, with consumer spending tilting toward services and B2B growth supported by inventory rebuilding.
Global GDP growth is expected to be 3.5% in calendar year 2022, previously 4.1% and it will be 3.1% in calendar year 2023.
In the third quarter, revenue growth was 10% year over year, with double-digit yield improvement for FedEx Express and FedEx Freight, close behind with FedEx Ground at 9% year-over-year yield improvement.
In the United States, our package revenue grew 9% in Q3 on strong yield improvement of 10%.
We executed on our peak pricing strategy in the month of December, delivering more than $250 million in peak surcharge revenue.
For the quarter, revenue increased 23% year over year, driven by a 19% increase in revenue per shipment.
Seven new countries will now be connected on a next-day basis within Europe, while 14 countries will be expanding our noon delivery coverage.
Additionally, our new modernized FedEx Ship Manager, which is our online shipping application, has now been rolled out in more than 153 countries.
These challenges subsided during February, resulting in third quarter adjusted operating income of $1.5 billion, up 37% year over year on an adjusted basis.
First, labor market conditions, although much improved, once again had a significant effect on our results at an estimated $350 million year over year, which was primarily experienced at Ground.
For the third quarter, that was primarily due to higher rates for both purchase transportation and wages.
The implications from the omicron variant surge reduced third quarter operating income by an estimated $350 million, predominantly at Express, as it influenced customer demand and pressured our operations, resulting in constrained capacity, network disruptions and lower volumes and revenue.
The third quarter had favorable year-over-year comparisons for variable compensation of approximately $380 million, including the one-time Express hourly bonus last year and significantly less impactful winter weather that lead it to $310 million.
Ground reported a 10% increase in revenue year over year, with operating income down approximately $60 million and an operating margin at 7.3%.
While pressures from constrained labor markets began subsiding, the effect was still significant at an estimated $210 million year over year, predominantly due to the higher purchase transportation and wage rates.
A 9% yield improvement partially offset these headwinds, and our teams remain very focused on improving ground performance, as Raj outlined earlier.
Express adjusted operating income increased by 27% year over year, driven by higher yields and a net fuel benefit, with adjusted operating margin increasing by 100 basis points to 5.8%.
Express results also benefited in the third quarter from $285 million of lower variable compensation, as well as much less severe winter weather.
The strong results were partially offset by the headwinds I mentioned earlier, with the omicron surge having the largest effect, especially during January, of an estimated $240 million.
Freight had another outstanding quarter, delivering an operating margin of 15%, 850 basis points higher year over year, and revenue for the third quarter increased 23% with operating income up over 180% despite the pressures from higher purchase transportation rates and wages.
We ended our quarter with $6.1 billion in cash and are targeting over $3 billion in adjusted free cash flow for fiscal 2022.
As such, I'm pleased to share the accelerated share repurchase program announced last quarter was completed during Q3 with 6.1 million shares delivered under the ASR agreement.
Total repurchases during fiscal '22 are nearly 9 million shares or 3% of the shares outstanding at the beginning of the year.
The decrease in outstanding shares resulting from the ASR benefited third quarter results by $0.06 per diluted share.
Also during the quarter, we made a $250 million, a voluntary contribution to our U.S. pension plan and have funded $500 million year to date.
We are affirming our full year adjusted earnings per share range at $20.50 to $21.50.
We have lowered our FY '22 capital-spending forecast from $7.2 billion to $7 billion.
Lastly, our projection for the full year effective tax rate is now 22% to 23%, prior to the mark-to-market retirement plan adjustments.
With that, we are all very much looking forward to sharing additional background in our upcoming investor meeting on June 28 and 29 in Memphis.

Summary:
Execution of our strategies resulted in substantially higher operating income for the quarter as Team FedEx delivered yet another outstanding peak season.
FedEx Freight once again delivered strong results with third quarter operating income nearly tripling year over year, driven by a continued focus on revenue quality.
For the third quarter, that was primarily due to higher rates for both purchase transportation and wages.
We are affirming our full year adjusted earnings per share range at $20.50 to $21.50.
We have lowered our FY '22 capital-spending forecast from $7.2 billion to $7 billion.