upTo_ x is used to specify a range of values less than but not including the value x. x can be of any type: Number, Boolean, Currency, Date, Time, DateTime, and String.
Examples
upTo_ 250
The range of all numbers less than 250.
upTo_ CDate (2000, 3, 17)
The range of dates before March 17, 2000, not including March 17, 2000.