FYI: Last year was a great year for global markets, but in relative performance terms, the average ETF surprisingly underperformed its peers if you consider data for all ETFs from every asset class against Morningstar-defined peer groups, which include mutual funds and ETFs.
However, the Morningstar numbers measure ETF performance on an equal-weighted basis. On an asset-weighted basis, accounting for larger funds in which more investors were invested in, ETFs outperformed.
Regards,
Ted
http://www.etf.com/sections/etf-strategist-corner/why-size-mattered-2017