Hang in there
Unless you are planning to leave/retire in the next few year just leave every thing as it is. I suspect that you are quite heavily invested in "managed" equities which are taking a hit worldwide at the moment. There will always be cycles like this which the fund managers are supposed to smooth but they are victims of the system too. Just ride the trough with the waves and dont try to second guess.
If you were planning to retire and withdraw the whole sum short term I would do at least two of the following.
1) Get into cash or bonds (but preferably not USD)
2)Forget the retirement, leave the money in the fund and apply to Mcdonalds.
3) Get down to the EK clinic for a double dose of valium because it is going to get really tense watching and waiting the 10 days that it takes Payroll to action your switching request whilst equities and the dollar screw themselves up into a little ball.
Good luck