Two-thirds of Genie scissors, one-third of Genie booms, and 60% of material processing products have an electric option.
We had an excellent quarter, earnings per share of $0.82 nearly quadrupled year over year, sales were up 26% year over year and we ended 2021 with a record backlog of $3 billion, up 122%, driven by strong customer global demand.
And focused cost management continued, resulting in 300 basis points of operating margin improvement.
On Execution, the team proactively managed supply chain disruptions to deliver sales growth of 26% year over year, aggressively managed costs to deliver a 430 basis point improvement in SG&A as a percent of sales and improved Genie's future cost competitiveness as our temporary Mexico facility is now producing telehandlers and continues to ramp up.
More than 8,000 of MP's machines are fitted with telematics hardware, and the number of dealers using customer and dealer integration, or CDI, has doubled in 2021.
The 60-foot J-Boom was named the contractors top 50 new product.
Looking at the fourth quarter, sales of $990 million were up 26% year over year and year-end market demand remained strong.
For the quarter, we recorded an operating profit of $70 million, more than double our operating profit of $32 million in the fourth quarter of last year.
Operating profit increased due to strong sales and $3 million of positive financial call-out.
Operating margins improved 300 basis points in the quarter, driven by actions to prudently manage and reduce costs.
Interest and other expense was approximately $8 million lower than the fourth quarter of 2020, due to a gain related to the relocation of our Genie administrative office and reduced debt levels.
Our effective tax rate of approximately 15% benefited from discrete items, including the favorable resolution of tax audits.
Our fourth quarter earnings per share of $0.82 increased nearly four times, representing a $0.61 improvement over last year.
The financial call-out, highlighted in this slide, represent a $0.16 benefit in the quarter.
First, we have not yet received an approved $39 million IRS refund.
MP continues to perform very well with sales of $454 million, up 24% compared to the fourth quarter of 2020 and the business ended the year with a backlog of $1 billion, which is nearly double that of a year ago.
MP delivered 13.8% operating margins by driving sales growth, while managing material costs and manufacturing headwinds.
AWP sales of $534 million increased by 30% compared to last year, driven by strong global end market demand.
AWP fourth quarter bookings of $922 million were up 23% year over year, while backlog at quarter end was nearly $2 billion, up 137% from the prior year.
AWP delivered improved operating margin of 4.8% in the quarter driven by strong customer demand and prudent expense management.
Earnings per share increased significantly from $0.13 to $3.07 or a $2.94 improvement.
Sales of $3.9 billion were up 26% year over year as end markets recovered.
Operating margin of 8.4% expanded 620 basis points, driven by strict expense discipline.
SG&A spending was $42 million lower year over year at 11% of sales, beating our 12.5% target.
We delivered a 32% incremental margin, exceeding our 25% target.
And we repaid $0.5 billion of debt, reducing net leverage to 1.1 times.
Included in our operating profit were $5 million of positive call-out.
Below the line, there were $29 million of noncash charges associated with our debt refinancing and term loan repayment.
This was partially offset by a $12 million cash gain related to our Genie administrative office relocation.
Our team members remain vigilant and aggressively manage all costs, generating $125 million of free cash flow in the year.
Our strong free cash flow generation and proceeds from the sale of our Terex financial services portfolio in February 2021, allowed us to repay $0.5 billion of debt this year, resulting in net leverage of 1.1 times.
We continue to invest in the business in 2021 with $60 million of capital expenditures.
Just this week, the board has approved an increased dividend of $0.13 per share as we continue to return cash to our shareholders.
We have ample liquidity with $867 million available to us at year end so we can manage and grow the business.
We anticipate earnings per share of $3.55 to $4.05 based on sales of approximately 4.1 to $4.3 billion.
AWP sales of 2.3 to $2.4 billion and MP sales of 1.8 to $1.9 billion reflects strong customer demand, but with the constraint presented by the supply chain.
We expect operating margin for the year to be in the range of 8.8 to 9.5%.
MP's margins of 14 to 14.5% will be relatively balanced throughout 2022, but the first quarter will be challenged by supply chain constraints.
AWP margins of 7.8 to 8.5% reflects significantly higher input costs peaking in the first quarter with price realization improving throughout the year as we work through the backlog.
For 2022, we are estimating free cash flow of 175 to $225 million, reflecting another year of positive cash generation.
We also estimate capital expenditures net of asset disposition will be approximately $90 million, the largest component being our Genie Mexico facility.
Our 2022 earnings per share outlook reflects the following assumptions: From an operational perspective, sales will increase as customer demand remains strong; pricing actions, along with manufacturing efficiencies, will offset cost pressures; SG&A reflects prudent investment in the business, including our new product development, engineering and digital initiatives and remains at 11% of sales.
In addition, we have an unfavorable tax impact as our full year effective tax rate is expected to normalize to approximately 20.5% as favorable discrete items from 2021 are not expected to repeat.
These two items together amount to a $0.30 per share headwind.
Taken together, these assumptions result in our 2022 earnings per share outlook of $3.55 to $4.05.

Summary:
We had an excellent quarter, earnings per share of $0.82 nearly quadrupled year over year, sales were up 26% year over year and we ended 2021 with a record backlog of $3 billion, up 122%, driven by strong customer global demand.
Our fourth quarter earnings per share of $0.82 increased nearly four times, representing a $0.61 improvement over last year.
We anticipate earnings per share of $3.55 to $4.05 based on sales of approximately 4.1 to $4.3 billion.