As we hear in every commercial (ever?)

> 
> Our best price, *ever*.
> 
> 
> 

Your thoughts please. Putting aside advertising allowances, should "ever" here mean "all time: past present and future", or should this be interpreted as "yet" (past/present). In *advertising* terms we must infer the latter (otherwise they'll contradict themselves next time they need a promotion), but from a *linguistics* perspective: what is the correct interpretation here?