Chief Financial Officer at Charter Communications
Thanks, Tom. Let's turn to our customer results on slides 6 and 7. Please note that we will continue to reference COVID-19-related financial impacts from 2020 and included again on slides 19 and 20 of today's presentation to help with year-over-year financial comparisons. We grew total residential and SMB customer relationships by 120,000 in the fourth quarter and by 939,000 in the last 12 months. Including residential and SMB, we grew our Internet customers by 190,000 in the quarter and by 1.2 million or 4.2% over the last 12 months.
Although our Internet customer growth remained strong in the fourth quarter, the business environment in which we are operating has not yet normalized. Similar to the third quarter, we saw both lower Internet churn and lower Internet connects than in fourth quarters of 2020 and 2019. Turning to video; video customers declined by 58,000 in the fourth quarter. Wireline voice declined by 154,000, and we added 380,000 mobile lines. As of the end of the fourth quarter, we had 3.6 million mobile lines.
And despite the lower numbers of selling opportunities from cable sales, we continue to drive mobile growth with our high-quality, attractively priced service rather than using device subsidies. Moving to the financial results, starting on slide 8; over the last year, we grew residential customers by 847,000 or 2.9%. Residential revenue per customer relationship increased by 2% year-over-year, driven by promotional rate step-ups, video rate adjustments that pass through programmer rate increases and $22 million of COVID-related impacts in the prior period.
These effects were partly offset by the same bundle and mix trends that we have seen over the past year, including a higher mix of non-video customers and a higher mix of lower-priced video packages within our base. Additionally, this quarter includes $31 million in adjustments related to sports network rebates, which we intend to credit to qualified video customers. These rebates are also reflected in lower programming expense this quarter with no impact to adjusted EBITDA. Also keep in mind that our residential ARPU does not reflect any mobile revenue.
As slide 8 shows, residential revenue grew by 5.1% year-over-year, reflecting customer relationship growth and ARPU growth. Turning to commercial, SMB revenue grew by 5.8%. This growth rate reflects COVID-related impacts of $8 million that negatively impacted the fourth quarter of 2020. Excluding this impact from last year, SMB revenue grew by 4.9%. Enterprise revenue was up by 3.2% year-over-year. Excluding all wholesale revenue, enterprise revenue grew by 6.1%. And enterprise PSUs grew by 5.3% year-over-year, a bit faster than last quarter.
Fourth quarter advertising revenue declined by 28.2% year-over-year, primarily due to strong political revenue in the fourth quarter of 2020, partly offset by COVID impacts last year. When compared to the fourth quarter of 2019, advertising revenue increased by 3.3%, primarily due to our growth in advanced advertising capabilities, partly offset by lower local ad revenue, particularly automotive. If you exclude automotive, fourth quarter advertising revenue grew by 13.3% over the fourth quarter of 2019. Mobile revenue totaled $632 million with $266 million of that revenue being device revenue.
Other revenue declined by 6.2% year-over-year, driven by lower levels of CPE sold to customers. In total, consolidated fourth quarter revenue was up 4.7% year-over-year. And when excluding advertising, which benefited from political revenue in the fourth quarter of 2020, revenue grew by 6.4%. Moving to operating expenses and EBITDA on slide 9; in Q4, total operating expenses grew by $203 million or 2.7% year-over-year. Programming costs decreased by 0.5% year-over-year due to a decline in video customers of 2.3%, a higher mix of lighter video packages, a $31 million benefit related to sports network rebates that I mentioned earlier and $19 million of other favorable adjustments, all of which was partially offset by higher programming rates.
Excluding both of the adjustments I just mentioned, programming costs grew by 1.2%. Looking at the full year 2022, we expect programming costs per video customer to grow in the mid-single-digit percentage range. Regulatory, connectivity and produced content grew by 11.3%, primarily driven by higher Lakers RSN costs, partially offset by lower original programming costs and regulatory and franchise fees. The Lakers cost growth was primarily driven by the delayed start of the NBA season in 2020, which drove fewer Lakers games charges in Q4 of '20, making for a challenging comparison to this year.
Excluding RSN costs from both years, regulatory, connectivity and produced content declined by 3.5%. Cost to service customers declined by 0.5% year-over-year compared to 3% customer relationship growth. The decline was driven by lower transaction costs, mostly offset by previously announced wage increases, which will ultimately provide all hourly employees at Charter a starting minimum wage of $20 per hour by the end of the first quarter. Marketing expenses grew by 4.3% year-over-year. Mobile expenses totaled $724 million and were comprised of mobile device cost tied to device revenue, customer acquisition and service and operating costs. And other expenses declined by 6.5%, driven primarily by lower advertising sales expense year-over-year, given the decline in political ad revenue this year and a onetime corporate cost in the prior year period.
Adjusted EBITDA grew by 7.7% year-over-year in the quarter. Turning to net income on slide 10; we generated $1.6 billion of net income attributable to Charter shareholders in the fourth quarter versus $1.2 billion last year. The year-over-year increase was driven by higher adjusted EBITDA. Turning to slide 11; capital expenditures totaled $2.1 billion in the fourth quarter, in line with last year's fourth quarter spend although the components of that spend were a bit different. Upgrade and rebuild grew by $66 million year-over-year due to plant replacement in those portions of our footprint that were damaged by Hurricane Ida.
Scalable infrastructure spends declined by $45 million, given a stabilized level of network traffic growth and investments made earlier this year. We spent $127 million on mobile-related capex, which is mostly accounted for in support capital and was driven by investments in back-office systems and mobile store build-outs. For the full year 2021, cable capital intensity was lower than in 2020 and in line with our outlook. As we look to the full year 2022, we expect cable capital expenditures, excluding capital expenditures associated with our rural construction initiative, to be between $7.1 billion and $7.3 billion.
We hope to spend about $1 billion in 2022 on capital expenditures related to our rural construction initiative or our construction within census block groups that are defined as rural. That spending includes our RDOF and other subsidized rural construction projects such as ARPU-related bills and spend associated with extending our plant to rural homes adjacent to our subsidized builds that our network does not reach today. We may not reach that targeted spend given a number of factors, including pull permitting and equipment and labor availability.
Conversely, we continue to bid on additional broadband stimulus projects that could increase 2022 capital spending for overall construction initiative. Given the variables, our actual rural construction initiative spending may differ meaningfully from our target. As Tom mentioned, the expansion of our footprint into rural areas will help us drive additional customer growth and financial returns. And we view our rural construction initiative as similar to or equivalent to acquiring a rural cable operator. We plan to begin disclosing additional operating information associated with our rural construction initiative in 2022.
Turning to Mobile; we expect our full year 2022 mobile capital expenditures to be about $100 million less than our full-year 2021 mobile capital spend, which totaled $482 million. Our 2022 mobile capital spend will consist primarily of back-office system spend, the start of our CBRS small cell construction and some additional store build-out. We will continue to update you on our capital spending expectations as the year progresses.
And as always, if we find new core cable, rural or mobile projects with attractive ROIs, we'll pursue them even if that means spending capital above our stated outlook. As Slide 12 shows, we generated nearly $2.3 billion of consolidated free cash flow this quarter, an increase of about $200 million or 10% year-over-year. We finished the third quarter with $91.2 billion in debt principal. Our current run rate annualized cash interest pro forma for financing activity completed in January is $4.2 billion.
As of the end of the fourth quarter, our ratio of net debt to last 12-month adjusted EBITDA was 4.39 times. We intend to stay at or just below the high end of our 4 to 4.5 times target leverage range. During the quarter, we repurchased 7.6 million Charter shares and Charter Holdings common units, totaling about $5.3 billion at an average price of $702 per share. For the full-year 2021, we purchased 25.3 million shares at an average price of $683 per share for a total spend of $17.3 billion. And between September of 2016 and December of 2021, we have repurchased $56.8 billion or about 40% of Charter's equity at an average price of $452 per share.
Turning briefly to taxes; we expect to become a meaningful cash taxpayer in 2022. Subject to any corporate tax rate changes for the years 2022 through 2024, we expect our federal and state cash taxes to be approximately equal to our consolidated EBITDA less capital expenditures and cash interest expense multiplied by 23% to 25%. We expect the cash tax rate in 2022 to be in the mid- to high teens range -- percentage range, given some of our tax attributes that have carried over from 2021. Those estimates would include partnership tax distributions to advance new house that are captured separately in cash flows from financing in the financial statements.
There are multiple pull factors that impact what I just described, and we're always looking for ways to improve our cash tax profile. So we're looking forward to the rest of 2022 as we remain well positioned to succeed and grow given strong demand for our products, which is why we continue to aggressively build out more broadband passings and ensure that our network remains state of the art. Our well-proven strategy, which offers customers the highest quality products at very attractive prices, drives customer and share growth, free cash flow growth and shareholder value.
Operator, we're now ready for Q&A.