It may be hard to believe, but there was a time when the islands had a favorable trade balance and turned a sizeable profit. In the 1930s, under Japanese administration, Micronesia was doing a booming business. There was the giant sugar industry and phosphate mines, but its exports also included katusobushi, starch, pineapples, and marine products like shell and pearls. This was a period when island exports paid the cost of running the colonial government. Thousands of Japanese immigrants provided the bulk of the labor, while islanders watched the marvels worked on their islands.