A floating-point constant is a literal or named  constant  with  one  or
  more  decimal  digits,  either positive or negative, an optional decimal
  point, and an exponent of 10 (E notation).  If the default data type  is
  INTEGER, a decimal point or an E is required or BASIC treats the literal
  as an integer.  If the default data type is DECIMAL, an E is required or
  BASIC treats the literal as a DECIMAL.