WASHINGTON (NEXSTAR) - Some California lawmakers are calling for an update to a federal homelessness program, saying the current funding formula doesn't match the needs of some cities.  Congressman Scott Peters (D-Calif.) says San Diego isn't getting its fair share of funding to fight homelessness.  "Our homelessness in absolute numbers is somewhere third to fifth in the country, and the funding we get from this formula has been 15th to 18th, depending on the year. And we just want it to match up," Peters said.  That formula is how the Department of Housing and Urban Development determines funding for cities under its Continuum of Care grant program, which funds permanent housing and other services nationwide. Peters says it's outdated, prioritizing the age of housing over a city's number of homeless people.  "Nothing could be less related it seems," Peters said.  Peters has pushed to change the formula for more than a decade.  "It's hard to make change in Washington, but we really need leadership from the White House, and we're hoping to get it," Peters said.  Peters and other San Diego area lawmakers recently sent a letter to HUD, asking the agency about its timeline to make a change. But updating the formula isn't so simple.  "Because unless there's a lot more money, there's always communities that win and communities that lose," Ann Oliva said.  Oliva used to run HUD's grant program. She's now the CEO of the National Alliance to End Homelessness. She agrees the formula is old but says updating it could hurt people already benefiting.  "People with disabilities, people who have high service needs, veterans, families, young people who really need that housing," Oliva said.  Oliva says more funding overall from Congress would help.  "The question to ask is how do we lift all boats," Oliva said.  HUD said in a statement its intent is to "continue to fund projects that are currently serving people to avoid having them experience homelessness again."