My portfolio of investments under-performed the major stock indices.
Common usage of portfolio to refer to a collection of investments seems etymologically wrong, since a portfolio is literally a portable collection of leaves or sheets (e.g., of paper).
"Portfolio" seems properly suited to describe a collection of written, drawn, or printed work that one would actually carry around, typically to showcase or sell one's creative work.
(I imagine the use of "portfolio" to describe investments originated in the era in which the ownership of securities took the form of stock or bond certificates, or other written contracts, which one might indeed collect in a portfolio. Though even then the prefix port seems as odd as the idea of carrying around a folio of one's securitized property. Why was it not simply an "investment folio?")
What is a more appropriate word for a collection of investments that could contain real estate or valuable objects that are neither portable nor sheet-like?