If you are making your IRA or 401k contributions throughout the year you may want to consider pulling them forward to the beginning of the year. The longer you have your money invested the longer it has to grow, earn dividends, and compound. Yes, market timing could be a consideration but that assumes you know the exact day when prices are low for you to make your deposits. That's not happening.
Example 1:
Deposit: $5,000 into IRA
Beginning of Year
Average Return: 7%
20 years
Total: $219,325
Example 2:
Deposit: $5,000 into IRA
End of Year
Average Return: 7%
20 years
Total: $204,977
Making deposits at the end of the year versus the beginning of the year is an illustration of an economic term called "opportunity cost." The opportunity cost here is $14,348. To get to the same $219,325 with end of year deposits would require earning an additional .6% each year or saving $350 more each year. Start planning now for 2013.