LANSING – Michigan retailers raised their forecasts for summer after posting increased sales in May, according to the Michigan Retail Index, a joint project of Michigan Retailers Association (MRA) and the Federal Reserve Bank of Chicago.

“Good sales performance for two consecutive months helped lift the spirits and forecasts of Michigan retailers,” James P. Hallan, MRA president and CEO, said Wednesday. “Warm weather, higher consumer confidence, a stronger housing market and gasoline prices below $4 during the month all contributed to improved retail sales.”

The May Michigan Retail Index found that 50 percent of retailers increased sales over the same month last year, while 31 percent recorded declines and 19 percent saw no change. The results create a seasonally adjusted performance index of 54.9, up from 54.0, in April. A year ago May it was 61.9.

The Index gauges the performance of the state’s overall retail industry, based on monthly surveys conducted by MRA and the Federal Reserve. Index values above 50 generally indicate positive activity; the higher the number, the stronger the activity.

Looking forward, 64 percent of retailers expect sales during June–August to increase over the same period last year, while 9 percent project a decrease and 27 percent no change. That puts the seasonally adjusted outlook index at 76.6, up from 68.1 in April. A year ago May it stood at 77.5.

At the national level, May retail sales excluding autos, gasoline and building materials increased as well, rising 0.3 percent, according to the U.S. Commerce Department.

Northern Michigan retailers showed the greatest improvement in sales throughout the state, with 75 percent of respondents reporting gains.