By Chip Castille, Managing Director, BlackRock
What makes a good rule of thumb? It should be memorable, pithy and, above all, useful. It also shouldn't overreach; it just gives good guidance. "Measure twice, cut once" is a great example. It doesn't try to explain carpentry. It just reminds us to take our time, be precise and avoid making a mistake that can't be undone. (Not bad for four words.)
What makes a bad rule of thumb? How about this: it doesn't work. Or worse, it brings about exactly the opposite of what you intended. Retirement is full of advice that sound reasonable but may be bad for your retirement health. Here are three to be wary of:
Rule of Thumb #1: Save 3% of Salary for Retirement
The most frequent auto-deferral rate into a 401(k) is 3% of pay, probably because it typically maxes out the company match. Unfortunately, 3% is just not going to get the job done.
Think of it this way: you will likely work for about 40 years and retirement can last up to 30. That means 40 years of pay checks need to be spread across 70 years. Common sense suggests that 3% (even with a company match) is not going to be enough provide the spending you'd like once you're in retirement.
Our recent research suggests that 10 to 13% is more reasonable. If that sounds like a lot, think of it this way: paying your future self 13% of your current pay can buy you 30 years of retirement spending. It may actually be a bargain.
Rule of Thumb #2: The 4% Drawdown
Let's say you retire with one million dollars in savings. One of the most common rules of thumb is that the first year you should withdraw 4%, or $40,000. Next year, add a cost of living adjustment, say 2.5%, and take out $41,000. And so on.
The risk here is that if the market moves against you, the odds increase that a rigid withdrawal plan will increase the odds of running out of money. If the market rallies, the opposite can happen and you will leave behind a large unspent surplus. (Great for your heirs, of course, but you would have enjoyed retirement less than you could have.)
So what's a better rule of thumb? Probably one based on a dynamic amount, a percentage of your portfolio. You may have less to spend some years, and more others, but the risk of spending down your assets is substantially reduced. What's more, as you get older and have a shorter retirement period to fund, you can increase the percentage.