As more companies posted online jobs for new employees, the Monster Employment Index increased one point in May. This is the fourth consecutive monthly gain.

The index has displayed a rising demand in 12 of the 20 industries tracked by Monster, while four remained flat and eight declined. The Monster Index has been compiled from the jobs posted on a number of employment sites including Monster. com.

Breaking down the industry sector, number of jobs has increased in the health-care and social assistance area, which increased 11 points to 102. Retail trade increased 3 points to 140 while wholesale trade grew by one point. The manufacturing, information and finance sectors were all flat.

Looking at the year over year data, which eliminates seasonal factors that distort month to month gains in all of the 28 metro areas tracked by Monster showed greater online jobs demand. The largest gains were in Portland, where the Monster Index rose 44% to 88 in May.

The second largest gainer is the Boston with increased index 36% to 79. Some 13 additional cities, including Atlanta, Chicago, Minneapolis and Pittsburgh had year over year growth of 20% or more. "Now you can really say it's a trend", said Jesse Harriott, a Senior Vice President at Monster. com Worldwide.