Annual time series data back to 1970 is available from key database UNCTADstat
Major publications include:
Least developed countries report (UNCTAD) 1984-2012 HC 61.U6 and Online (1996-)
Trade and development report 1982-2012 HF 1416 and Online (1996-)
UNCTAD handbook of statistics Online (2002-)
World investment report 1996- HG 4538.W6 and Online (1991-)
Also various databases, including:
World Integrated Trade Solution (WITS) - data on international trade, tariff and non-tariff measures. Uses UN Comtrade data (you must register in order to access data)
TCdata360 database which offers current & historical data collected from many sources covering trade (annual), investment, innovation
LPI (Logistics Performance Index) for benchmarking country trade logistics performance
International Trade Costs (World Bank/ESCAP). Data from 1995-2014 for countries around the world
Doing business in ... comparative data (and publications) 2002- on business regulations & their measurement for countries around the world
Including International Trade & Tariff Data and Trade Monitoring Database which provides detailed information on trade measures implemented by WTO members and observers since October 2008.
Interesting Trade Cost Index database looking at changes in trade costs for 43 economies 2000-2018, with data at sector level
Also Research Database on Trade & Gender
Flagship publications:
World trade report Online (2003-)
World trade statistical review Online (2016-) continuation of: International trade statistics Online (2001-2015)