With the looming specter of not only the fiscal cliff with rising capital gains tax rates, but also the onset of the new 3.8% Medicare tax on net investment income in 2013, many investors have been looking to harvest capital gains before the end of the year.
The strategy is somewhat controversial, inasmuch as most taxpayers (and their accountants) have long since trained themselves to avoid ever paying taxes sooner than they absolutely have to, maximizing the value of tax deferral according to the basic principles of the time value of money. Nonetheless, the math of the situation with rising tax rates is quite straightforward, and in such environments it can require significant appreciation in a short period of time to make deferral worthwhile.