Can you give any sources?
US Forests History and trends (FAO): www.fao.org/docrep/meeting/x4995e.htm
WorldBank has numbers for global trends but only with data starting in 1990 and for forest surface: https://data.worldbank.org
It shows a slight decline, but as FAO points out, forest density (trees pr sqmt) is also growing so forest surface area numbers don't tell the whole story.