One perplexing question investors often face is whether to invest their capital all at once in the form of a lump sum or position it in fixed amounts at regular intervals – a strategy commonly referred to as dollar-cost averaging. Studies have found that investing the entire lump sum at once generally leads to slightly better returns over the long-term. Practically speaking, however, many investors prefer the short-term risk reduction dollar-cost averaging can provide.

http://www.letsmakeaplan.org/blog/view/lets-make-a-plan-blogs/investing-in-a-volatile-market-the-case-for-dollar-cost-averaging