The gap between high- and low-income families is wider in New Mexico than in most of the nation and has increased more in the state than in most places, according to a new study.

The average incomes of the wealthiest one-fifth of New Mexico's families rose 29 percent between the late 1990s and the mid-2000s while the incomes of the poorest one-fifth remained relatively unchanged. Their incomes increased 1.7 percent during that time, but the study said that wasn't statistically significant.

The middle one-fifth of families had a 7 percent increase in average income, according to the study released Wednesday by the Washington, D.C.-based Center on Budget and Policy Priorities and the Economic Policy Institute.

There also has been a widening nationally of the income gap between rich and poor families. The study said a variety of economic factors and government policies played a role, including globalization, losses of higher-paying manufacturing jobs, tax changes benefiting the upper income and stagnant wage growth for many American workers.

With the economy slowing, low- and middle-income families will be hurt the most in New Mexico, according to Gerry Bradley, an economist and research director for New Mexico Voices for Children, a social advocacy group based in Albuquerque.

"Policies that the state put in place in 2007 — raising the minimum wage, creating the state Working Families Tax Credit and increasing unemployment benefits — were good policies and will help some, but it's like a garden hose compared to the tidal wave impact of the economy," Bradley said in a statement.

The state minimum wage went to $6.50 an hour in January, up from $5.15, and it will increase to $7.50 in January 2009.

New Mexico's upper-income families had an average income of $118,608 in 2004-2006. That's eight times larger than the average income of the poorest families, $14,798.

The wealthiest had incomes 2.8 times greater than the $41,797 average income of the middle fifth of New Mexico's families.

Only five states had a larger income gap as measured by that ratio of top-to-bottom and top-to-middle incomes.

The disparity in incomes in New Mexico also grew more than in all but a few states, according to the study.

In 1998-2000, high-income families had average incomes that were 6.3 times larger than the lowest-income families, and that top-to-bottom income ratio increased by 1.7 to reach eight in 2004-06. Only two states — Mississippi and Alabama — had larger changes in the income disparity between the top and bottom fifth of families.

ON THE WEB

• Center on Budget and Policy Priorities: www.cbpp.org
• Economic Policy Institute: www.epi.org
• New Mexico Voices for Children: www.nmvoices.org