2017 Investment Sales Volume

What was the total investment sales volume (US$) for the following fiscal years?

total investment sales volume*; $ in billions

Source: CPE listing of Real Estate Education Programs, which appeared in the April 2017 issue of Commercial Property Executive.
*Based on responses to a CPE-MHN survey
Source: CPE-MHN listing of Most Powerful Brokerage Firms, which appeared in the June 2017 issues of Commercial Property Executive and Multi-Housing News