Switzerland Mushroom Production is set to reach 7,180 Metric Tons by 2026 from 7,310 Metric Tons, is expected to fall by 0.3% per year. Since 1966, the supply was up 3.5% year on year at 12,424,000 Metric Tons. Japan, the United States and Poland respectively came in numbers 2, 3 and 4 in this ranking.