OTTAWA - Canada is rapidly catching up to the United States as a country divided between haves and have-nots, according to a study issued Tuesday by the Conference Board.

The Conference Board says income inequality has been rising more in Canada than in the United States since the mid-1990s, and faster than in many peer countries.

In fact, the think-tank says Canada had the fourth-largest increase in income disparity among a sample group of 17 advanced economies in the period between the mid-1990s and the late 2000s.

"Even though the U.S. currently has the largest rich-poor income gap among these countries, the gap in Canada has been rising at a faster rate," said Anne Golden, the board's chief executive.

"High inequality raises a moral question about fairness and can contribute to social tensions," she added.

Overall, income inequality rose in 10 of the countries sampled, rising fastest in Sweden, Finland and Denmark.

Canada was next. Its Gini index, a complicated formula which measures income deviations from a perfectly equal distribution, rose 9.2 per cent to 0.320.

By contrast, the U.S. had the highest income inequality of the group with a Gini reading of 0.378.

The Conference Board notes that Canada's index number put it in group of countries considered to have a medium range of income inequality.

A reading above 0.4 would designate high levels of income inequality, and under 0.3 indicates a low income gap.

Overall, the Conference Board says income inequality has increased in countries representing 71 per cent of the world's population. Twenty-two per cent live in countries where inequality is declining.