The nature of SCI's business is such that many customers prepay for their funeral requirements, thereby taking the burden off of their families. Because this money is not yet earned, it is classified on the balance sheet as "deferred revenue" (similar to how a football team receives cash upfront for a game that has not yet been played, or a home builder gets a down payment for a house not yet built). To maximize returns, SCI invests part of this money in the market.
Unfortunately, much of this money has been lost. The company has unrealized losses of over $600 million in these accounts! With SCI having a market cap of just $1.2 billion, this is not an insignificant amount.
We've discussed before how deferred revenue can be a useful gauge in determining what a company's future earnings will look like. Investors who don't consider how that deferred revenue is invested can end up way off in their valuations!