It’s looking like it could be a while before SoftBank Corp. ’s $22 billion bet on Sprint Corp. pays off.

A year and a half after the Japanese technology conglomerate bought control of the American wireless carrier with big plans to shake up the business and steal customers, Sprint still finds itself struggling in third place in the U.S. market, a point made clear by the company’s year-end results.

Sprint lost 205,000 mainstream “postpaid” cellphone customers in the final three months of the year, posted a higher monthly customer loss rate and wrote down the value of its trademark by $1.9 billion. The results extended a streak of customer losses, and revenue declined 1.8% over the past year.

There were bright spots. While Sprint is losing customers, the size of the losses is shrinking. And while its free cash flow—the cash produced by its operations minus capital expenditures—was a negative $1.8 billion, that was about $1 billion smaller than its deficit in the year-earlier quarter. The carrier predicted earnings before some adjustments—a figure it previously thought could be flat—would grow between 5% and 7% in 2015.

Still, Sprint has a lot of work to do to demonstrate it can be an effective competitor in the U.S. wireless market.