Fig. 1From: The health impact of trade and investment agreements: a quantitative systematic review and network co-citation analysisNumber of RTAs, 1950–2010. Notes: Solid black line represents cumulative number of RTAs in force; grey bars show RTAs entered into force per year. Data extracted from the World Trade Organization’s Regional Trade Agreements Information System on 15 February 2016. See bibliography for full reference [57]Back to article page