There was a man who had worked at a factory for twenty years. Every night when he left the plant, he would push a wheelbarrow full of straw to the guard at the gate.
The guard would look through the straw, and find nothing and pass the man through.
On the day of his retirement the man came to the guard as usual but without the wheelbarrow.
Having become friends over the years, the guard asked him, "Charlie, I've seen you walk out of here every night for twenty years. I know you've been stealing something. Now that you're retired, tell me what it is. It's driving me crazy."
Charlie simply smiled and replied, "Okay, wheelbarrows!"