We do have small cap representation but it's in proportion to the entire market, hence I called it a «Total Market» position. (thedigeratilife.com)
The MSCI World ex USA Index captures large and mid cap representation across developed market countries, excluding the U.S.. (hartfordfunds.com)
Using the S&P 500 would be a good choice, not only because it has broad large - cap representation of the market, but also because it has a long history. (investopedia.com)