In recent months, one particular event has instilled fear and even panic in households across the nation: the arrival of the 401(k) statement. Those who can bring themselves to open the envelope or click on the e-mail version are often stricken by columns of minus signs and descending numbers. As always, though, it is important to put the numbers in perspective. According to the Employee Benefit Research Institute, people with more than $200,000 in their accounts have still managed an average increase of 161 percent in their balance since 2000.