(CBS) — Charter Communications Inc. (NASDAQ: CHTRM) is the largest provider of internet and television service in the United States.

Its stock has skyrocketed in recent years, rising more than 400% since 2013.

That surge in value came as it began selling the majority of its holdings in several schools across the country, including charter schools in California and Florida.

And as the number of charter schools rose in recent decades, so too did the number and size of charter school operators, according to the U.C.L.A. Charter School Transparency Project.

The group examined more than 1,000 charter school records in more than 300 states, and found that more than one-third of charter operators are now based in California, with a majority of operators based in Texas, according the project.

The majority of charter operations are located in California.

And charter school principals are now more likely to be employed by the company than they were even 10 years ago.

 That makes Charter Communications the most highly profitable private company in the U-S., according to an analysis of its earnings, financial reports and company filings by the nonpartisan nonprofit Center for Responsive Politics.

In addition to its charter schools, Charter Communications owns satellite TV, cable television and internet providers, satellite and cable TV distribution, telecommunications companies, and telecommunications services for businesses, according its most recent SEC filing.

Charter Communications’ annual profits are estimated at more than $300 million, according an SEC filing last year.

Its net income was $2.5 billion in fiscal year 2018, the most recent year for which data are available.

Its $1.5 trillion in assets were valued at $4.4 billion at the end of the fiscal year.

The company’s $1 billion in cash is largely derived from dividends and other stock-based compensation, according SEC filings.

The company is owned by two brothers who have made it their mission to make charter schools the largest employer in the nation.

Tom and Richard Branson have invested $2 billion in charter schools over the past decade.

The Branson family is also one of the largest investors in private prisons.

Charter Communications employs roughly 4,200 people in California alone.

On Tuesday, Charter’s CEO, Mike Roberts, told investors the company was on track to have a profitable year, and he had no reason to doubt it.

“We have a plan to grow Charter and we’re on track,” Roberts said.

“And, as we have, we will be profitable.”

Roberts did not respond to a request for comment about how Charter’s earnings and cash could possibly be in any danger.

What do you think?

Did Charter make a lot more money off schools than it was getting back?

Do charter schools make too much money?

Tell us your thoughts by commenting below.