WASHINGTON (AP) _ A burst of year-end hiring returned the nation's unemployment rate to 4.3 percent in December and helped produce in 1998 the strongest peacetime labor market in four decades.

The seasonally adjusted rate, down from 4.4 percent in November, returned to the level reached in April and May and, before that, in 1970, the Labor Department said today.

For the year, unemployment averaged 4.5 percent, the lowest since 3.5 percent in 1969 during the Vietnam War. The 1998 mark was the lowest peacetime rate since 1957, when it averaged 4.3 percent.

In December, employers added 378,000 jobs to their payrolls _ the most in 15 months and nearly double what analysts anticipated. Some of the gain reflected unseasonably warm weather, which produced a huge 104,000 gain in construction but much of it reflected the U.S. economy's resilience in the face of the global economic slump that began in Asia a year and a half ago.