Christianity in its Global Context, published in June of 2013, is an exhaustive 100 page report on missions, evangelism and Christian growth from 1970 on out to 2020. It is the resource for the most accurate statistics available.
A page from World Christian Trends (2001) which gives alarming statistics we all should be aware of. For example, did you know that if you make more than $10,000 USD per year, you are in the top 9% of the wealthiest people in the world?
This famous article explains the two structures that comprise The Church—the local expression and the mobile expression—and how missions organizations' and local congregations' unity and symbiotic relationship is essential.