WASHINGTON — The nation's health care tab is on track to hit $4.6 trillion in 2020, accounting for about $1 of every $5 in the economy, government number crunchers estimate in a report out today.

How much is that? Including government and private money, health care spending in 2020 will average $13,710 for every man, woman and child, says Medicare's Office of the Actuary.

By comparison, U.S. health care spending this year is projected to top $2.7 trillion, or about $8,650 per capita, roughly $1 of $6 in the economy. Most of that spending is for care for the sickest people.

The report from Medicare economists and statisticians is an annual barometer of a trend that many experts say is unsustainable but doesn't seem to be slowing down. A political compromise over the nation's debt and deficits might succeed in tapping the brakes on health care, but polarized lawmakers have been unable to deliver a deal.

The analysis found that President Barack Obama's health care overhaul would only be a modest contributor to growing costs, even though an additional 30 million people who would be otherwise uninsured stand to gain coverage.

The main reasons that health care spending keeps growing faster than the economy are the high cost of medical innovations and an aging society that consumes increasing levels of service.