New figures show Australian hospital admissions increased from 8.1 million to 8.5 million in a year.

The Australian Institute of Health and Welfare figures, in its report titled Australian Hospital Statistics 2009-10, shows the biggest increase in admissions was at private hospitals.

AIHW spokesperson Jenny Hargreaves said there were 5.1 million admissions in public hospitals and over 3.5 million in private hospitals.

"In the five years to 2009-10 admissions to public hospitals rose by an average of 3.5 percent each year, while admissions to private hospitals increased by an average of 5 percent a year," she said.

"This increase was accompanied by a drop in the average length of time overnight patients spent in hospital, to 5.9 days in 2009-10 after being 6.2 days for the four previous years."

Same-day admissions made up 58 percent of total hospital admissions with 51 percent in public and 68 percent in private hospitals.

The figures also show waiting times for public elective surgery was up slightly from 34 to 36 median days while there were 1.9 million overall admissions for elective surgery.

Rates for elective surgery in public hospitals remained steady at about 30 admissions per 1000 people while rates for elective surgery in private hospitals was up from 49 to 55 per 1000 people.

Public hospitals provided about 7.4 million accident and emergency services, up from 7.2 million the previous year.

The report states about 70 percent of patients were seen within the recommended time for their triage category, including 100 percent of patients requiring immediate treatment.

There were 1326 hospitals in Australia in 2009-10, with 753 public hospitals accounting for 67 percent of hospital beds, or 56,900 beds, and 573 private hospitals accounting for 33 percent or 28,000 beds.

The report shows public hospitals spent about $33.7 billion in 2009-10, which adjusted for inflation means a 5.4 percent average increase in spending each year from 2005-06.