First published by Money Metals here: https://www.moneymetals.com/news/2017/04/25/silver-mining-productivity-falls-001054

After the Primary Silver Mining Industry enjoyed a brief increase in productivity over the past two years, it fell to the lowest ever in 2016. The reason the primary silver mining industry’saverage yield increased in 2014 was due to the addition of Tahoe Resources high-grade Escobal Silver Mine.