The figure that got the most attention in Time Warner Cable's (NYSE: TWC) latest quarterly earnings announcement was 54,000, which represents the number of video subscribers who joined the service over the final three months of 2015. That small uptick was enough to push TWC's annual customer additions into positive territory for the first time since 2006.

But there were several other important numbers in the Q4 earnings release that investors should know. Here are five of the biggest:

$128 average revenue per user (ARPU)
The average monthly revenue that TWC generates from each of its customers ticked higher by 1% this quarter, to $128. That gain was powered by strong high-speed Internet sales as opposed to cable services growth, though.

Data source: TWC investor presentation.

The company benefited from higher Internet data and equipment rental charges, along with a greater percentage of subscribers opting for the higher-priced tiers of service. The cable segment's ARPU, meanwhile, ticked down as more recent customers tended to sign up under lower-priced video plans.

$130 million increase in programming and content costs
Programming costs spiked higher by 10% for the fourth quarter and for the full year, marking a big acceleration from 2014's 7% increase. Management blamed rising contractual fee increases, which TWC pays to network operators for their content.

TWC's programming expenses are growing at a faster pace than peers. Charter's (CHTR -1.63%) programming costs ticked up by 8% last year while Comcast (CMCSA -0.25%) paid just 7% higher costs in 2015.

TWC executives said in the earnings conference call that they don't see any major change to their double-digit growth pace on the horizon. But presumably, if its proposed merger with Charter goes through, the combined entity will have more leverage in programming negotiations so that overall cost growth gets closer to Comcast's more manageable pace.

$1.13 billion operating profit (down from $1.2 billion last year)
Those rising costs were the biggest driver behind operating expenses outpacing revenue growth. As a result, TWC's profitably fell this quarter. Operating margin shrunk to 19% from 21% a year ago on a 8% decline in earnings.

Operating income and adjusted earnings both fell as expense rose faster than sales. Data source: TWC investor presentation.

Again, this trend isn't likely to quickly reverse itself, at least not until cable subscriber growth is robust enough that TWC can start passing on more of its rising costs in the form of higher package prices.

13% and 19% declines in customer care calls and repair-related customer visits, respectively
That's why it's good news for the business that TWC's cable and Internet customer service metrics improved this quarter, as evidenced by double-digit drops in required call-ins and repair visits by technicians.

Image source: TWC.

Better customer service ultimately helps the company hold on to its user base for longer, and in fact management has noticed a sharp improvement in its churn, or cancellation, rate thanks to these customer experience improvements.

TWC executives have called this a major strategic focus for the year ahead, and they plan to devote more resources toward driving network reliability higher while reducing the need for customer calls and tech visits.

$4.5 billion capital expenditures
TWC spent $946 million, or 9% more, on capital expenditures this quarter, which it attributed to investments in equipment upgrades and network reliability and expansion.

That spending included deploying the TWC Maxx digital service to major metropolitan areas like Austin, Dallas, Raleigh, and San Antonio. The service is set to expand into new geographies in the coming quarters, which should continue to push capital expense higher.

Looking ahead, CEO Rob Marcus declined to give investors 2016 guidance due to the company's pending merger with Charter. But investors can at least expect to see positive subscriber momentum continuing, even if those gains are held back by rising operating costs and capital expenses this year.