Thieves have been stealing the 420 mile marker sign so often, the state's transportation department has changed it to "419.99" to try and stop the problem.
Amy Ford, a spokeswoman with the Colorado Department of Transportation, told USA Today that, "it's a traffic safety thing. It's a helpful thing to have these signs on the road. But people kept ripping them off."
The number 420 is often used as a reference to smoking marijuana.
The 419.99 sign has been put up within the last year.
So far, the Colorado Department of Transportation say it's been working.
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