Caterpillar Inc. says sales of its yellow-and-black equipment improved 32 percent in July when strong sales in Asia and North America drove the firm's third-straight positive month.

Caterpillar is disclosing its monthly sales figures in a filing with the Securities and Exchange Commission. They are considered an indicator of global economic health because Caterpillar is the largest maker of construction and mining equipment.

The company says equipment sales in the Asia Pacific region surged 41 percent, and North American sales improved 38 percent. But sales were up in every region. The smallest increase came in Europe, Africa and the Middle East where sales still increased 19 percent.

Caterpillar's engine and turbine sales were up 5 percent overall.