Jackson, Miss. ? More than 1 million fewer job advertisements were posted online in January than were displayed only two months earlier, according to a private research group.

Michele Sarin, manager of database analysis for the Conference Board, says the two-month decline is the sharpest drop since the group began tracking online help wanted data in 2005.

The board’s monthly Help-Wanted Online Data Series report said online advertised vacancies declined 506,000 in January to about 3.35 million ads. That followed a decline of 507,000 in December.

The data series tracks the number of jobs posted on more than 1,200 major Internet job boards and smaller Web sites that serve niche markets.

“I’m looking right now at all the data back to May 2005 and this is by far the largest (decline) and each of the two months is larger than all of the previous ones,” Sarin said.

Advertised vacancies dropped in all 50 states last month.