UPS stock is on sale right now. It may even go down a little more, short term. If you are holding for the long term, it will most certainly go up.
If you are doing $50/week towards UPS stock, you should also be doing $200-$250/week in a 401k with a balanced portfolio. If you are FT and working average hours 19-20% into 401K will get you at about the right spot.